MS CHAUHAN ADVANCE

250 Column (II) 7. Match the column I and II. Product Column (I) OH Reaction (a) ¾(¾1)O¾sO¾4 ® (p) (2) NaOH, H2O (b) ¾(¾1)B¾H3¾et¾h¾er ® (q) Cl (2) H2O2, NaOH, H2O OH (c) ¾C¾l2,¾H¾2O ® (r) OH OH (d) ¾C¾l2 ¾CC¾l4 ® (s) Cl Cl 8. (1) CH2 — OH HO OH (2) ¾H¾¾+ ® (B) ¾H¾¾+ ® ( A) OH D D OH (3) ¾H¾¾+ ® (C) (4) ¾H¾¾+ ® (D) OH OH D D Sum of molecular mass of A, B, C, D (i.e. A + B + C + D) is equal to : https://t.me/studyzee

251 9. (1) C 2FClBrI ¾ H¾2 ®( A) (exclude stereoisomer) (all isomers) Ni (2) C 4H 8(alkene) ¾ H¾2 ®( B) (exclude stereoisomer) (all isomers) Ni Total number of products A and B (i.e. A + B) is equal to : 10. Reaction 2 Reaction 1 CH3 CH3 H Br H Br CH (trans) ¾B¾¾r2 ® (Q) CH (cis) ¾B¾¾r2 ® (P) CH CCl4 H Br CH CCl4 CH3 H Br Reaction 4 CH3 CH3 H Br Reaction 3 CH3 CH H Br (trans) ¾B¾¾r2 ® (S) CH CH CCl4 (cis) ¾B¾¾r2 ® (R) CH3 CH CCl4 CH3 Sum of products P, Q, R, S (i.e. P + Q + R + S) is equal to : https://t.me/studyzee

252 11. Comprehension Vladimir Markovnikov rule : Alkenes undergo electrophilic addition reactions. It is triggered by the acid acting as a electrophile toward p-electrons of the double bond. Markovnikov’s rule states that when an unsymmetrically substituted alkene reacts with a hydrogen halide, the hydrogen atom adds to the carbon that has the greater number of hydrogen, e.g., CH3 CH3 + H – Cl ¾0¾¾°C ® Cl 1-methyl cyclopentene 1-chloro-1-methyl cyclopentane Mechanism : Step - 1 CH3 + H – Cl ¾r¾.d¾.s ® Å CH3 Cl Q Å CH3 Cl – ¾C¾¾l- ® CH3 (fast) Cl Step- 2 (fast) A. Which of the following is most reactive toward Markovnikov addition ? OO (a) (b) (c) (d) B. What is the energy profile for the given reaction ? (a) (b) E E Reaction co-ordinate Reaction co-ordinate (c) (d) E E Reaction co-ordinate Reaction co-ordinate C. In which of following reactions carbocation rearrangement is possible ? (a) (CH 3)2CH — CH == CH 2 ¾H¾¾Cl ® (b) (CH 3) 3C — CH == CH 2 ¾H¾¾Br ® 0°C 0°C /Cl4 (c) Ph — CH 2 — CH == CH 2 ¾H¾¾Br ® (d) All of these CCl 4 https://t.me/studyzee

253 D. Identify the major products r1, r2 and r3 in the given reactions. HBr CH3 H2O r1 HBr r2 CH3OH HBr r3 OH OD D2O CH3 CH3 OCH3 CH3 (a) , , OH OCH3 OD CH3 CH3 CH3 (b) , , Br OH CH3 CH3 (c) in all the reactions (d) in all the reactions E. In which of the following reactions, product is racemic mixture ? (a) CH 3 - CH 2 - CH = CH 2 ¾H¾¾Br ® CH3 C=C H (b) ¾H¾¾Br ® CCl 4 H CH3 CCl4 CH3 C=C CH3 ¾H¾¾Br ® (d) All of these (c) (cis) H CCl4 H F. In which of the following reactions, diastereomers will be formed ? CH3 CH3 (a) ¾H¾¾Br ® HD CH3 CCl4 CH || Br CH (b) ¾H¾¾Br ® CCl 4 (c) ¾H¾¾Br ® (d) All of these CCl 4 https://t.me/studyzee

254 12. Comprehension CH 3 — CH 2 — CH == CH 2 + CH 3OH HÅ CH 3 — CH 2 — CH — CH 3 ¾¾¾® | OCH 3 Consider the above reaction and answer A to E. A. What is electrophile in first step ? (b) H Å (d) HO Å Å (a) CH 3 Å (c) CH 3 — CH 2 — CH — CH 3 B. What is nucleophile in first step ? (b) 1-butene (d) CH 3 - O - CH 3 (a) CH 3OH (c) H 2O (b) H Å C. What is electrophile in second step ? Å Å (d) CH 3 — CH 2 — CH 2 — CH 2 (a) CH 3 Å (c) CH 3 — CH 2 — CH — CH 3 D. What is nucleophile in second step ? (b) CH 3OH (a) CH 3 — CH 2 — CH == CH 2 (d) CH 3 — O — CH 3 (c) H 2O (b) attack of electrophile H Å E. Which step is rate determining step ? (a) attack of nucleophile CH 3OH Å (c) attack of nucleophile H 2O (d) attack of electrophile CH 3 https://t.me/studyzee

13. Match the column I and II : 255 Column (II) Column (I) Br Conversion Reagent CH3 SO2Cl2 / hv (2 equivalent) (a) ¾® Br (p) CH3 CH2– Cl (b) Cl (q) NBS (2 equivalent) ¾® CH3 Br (c) Cl (r) NBS then SO2Cl2/hv ¾® CH3 CH2 –Cl (d) ¾® Br (s) SO2 Cl2 / hv then NBS https://t.me/studyzee

256 ANSWERS — LEVEL 2 1. (i) – A; (ii) – B; (iii) – G; (iv) – C; (v) – F 2. a – D; b – A, C; c – B, E; d – A, C, F; e – B, E, F; f – F; g – G; h – I, K; i – B, E, I; j – D, L 3. Reaction 1 : B, D; Reaction 2 : E, F, C Reaction 3 : I, A Reaction 4 : L, G Reaction 5 : B, L, C 4. a – C; b – D; c – A; d – F; e – I; f – J; g – E; h – H; i – B; j – G 5. a – p, q; b – r, s; c – r, s; d – p, q 6. a – r, s – z; b – p, s – y; c – p, s – y; d – q, s – y 7. a – r; b – p; c – q; d – s 8. A + B + C + D = 312 9. A + B = 5 10. P + Q + R + S = 8 11. A – b; B – c; C – d; D – b; E – d; F – d 12. A – b; B – b; C – c; D – b; E – b 13. a-q; b-p; c-s; d-r https://t.me/studyzee

257 4C HYDROCARBONS (ALKYNES) Level - 1 O || C — CH3 (1) 3NaNH2, 1. ¾¾PC¾l5 ® ( A) ¾¾min¾eral¾oil¾® (B) ; Product (B) is : (a) 0°C 70- 80% (2) HÅ 46% CH ==CH2 C ºº CH CH2 (b) (c) (d) 2. ¾C¾BC¾rl24® ¾(¾i) a¾lc.K¾O¾H ® ( A) ; Product (A) is : (ii) NaNH2 major (a) H 2C == CH — CH == CH 2 (b) CH 3 — C ºº C — CH 3 (c) CH 3 — CH 2 — C ºº CH (d) CH 3 — CH == C == CH 2 3. CH 3CH 2C ºº CH ¾¾lNiqa.N¾NHH¾23 ® I O J ¾¾H¾Å ® ( K) Et2O OH Product (K) of the above reaction is : C ºº C — Et O C ºº C — Et (a) (b) https://t.me/studyzee

258 C ºº C — CH2 — CH3 OH OH C ºº C — CH3 (c) (d) 4. CH 3 — CH 2 — CH 2 — C ºº CH + LiNH 2 ¾¾® ( A) ¾(¾CH¾3 )2¾SO¾4 ® (B) Lithium amide Give the structural formula of compound (B) : (a) CH 3 — (CH 2)2 — C ºº C — SO 3H (b) CH 3 — (CH 2)2 — C ºº C — CH 3 O || (c) CH 3 — (CH 2) 2 —C ºº C — CH 2 — O — S— H || O (d) CH 3 — CH 2 — C ºº C — CH 2 CH2 – CH2 – CH3 5. ; This conversion can be acheived by : (a) NaNH 2 , CH 3CHO (b) NaNH 2 , CH 3 — CH 2 — CH 2 — Br (c) KOH, CH 3 — CH 2 — Br (d) KOH, CH 2 — CH 2 || Br Br 6. Which alkyne will give 3-ethylhexane on catalytic hydrogenation ? (a) (b) (c) (d) All of these 7. Reactant P gives products Q or R. H (CH2)4 (CH2)4 H P Q or (H2C)4 H H R The possible reagents are : (I) 2Na liq.NH 3 (II) H 2 Pd CaCO 3(quinoline) (III) 2H 2 Pd C The correct statement with respect to the above conversion is/are : (a) Q is obtained on treatment with reagent (I) (b) R and Q are obtained on treatment with reagent (II) (c) R is obtained on treatment with reagent (I) (d) R is obtained on treatment with reagent (II) https://t.me/studyzee

259 8. Br — (CH 2)12 — C ºº CH ¾¾NaN¾H¾2 ® ( A) ¾C¾Laintad¾lly¾asrt® (B) ; Product (B) is : H (a) (b) H HH (c) (d) Br — (CH 2) — CH == CH 2 9. Ph — C ºº CH ¾M¾MeeOO¾¾H– ® Major product of the reaction is : Ph H Ph OMe (a) C ==C (b) C == C HH HH (c) Ph — C ºº C — OMe (d) Ph – C == CH2 Cl OMe | 10. Ph ¾ C ¾ CH 3 ¾3¾NaN¾H2® ( A) ; Product (A) is : | Product Cl sr (a) Ph ¾ CH == CH 2 (b) Ph ¾ C ººCH (c) Ph ¾ CH 2 ¾ CH 3 (d) Ph ¾ C ººCNa 11. Which combination is best for preparation of the compound (A) shown below ? CH3 H C — CH2CH2CH2C ºº CH (a) H3C CH3CH2 (A) CH3 H H C — CH2CH2CH2Br ¾Na¾C º¾º C®H ( A) C — CH2CH2CH2Br ¾Na¾C º¾º C®H ( A) (b) CH3CH2 CH3CH2 H CH3 (c) H3C C — Br ¾¾1¾. N¾aN¾H2¾, N¾H3¾® ( A) (d) H C — Br ¾¾1¾. N¾aN¾H2¾, N¾H3¾® ( A) 2. BrCH2CH2CH2C ººCH 2. BrCH2CH2CH2C ººCH CH3CH2 CH3CH2 12. Which one of the following is the intermediate in the preparation of a ketone by hydration of an alkyne in the presence of sulfuric acid and mercury (II) sulphate ? https://t.me/studyzee

260 (a) HO (b) (c) OH OH OH (d) 13. ¾A® ¾B® O O — CH2 — C ºº CH O O — CH2 — C ºº C — CH2 — CH2 — CH2 — Br To carry out above conversion, (A) and (B) respectively, are : (a) NaNH 2 ,Cl — CH 2 — CH 2 — CH 2 — Br (b) NaNH 2 , F — CH 2 — CH 2 — CH 2 — Br (c) NaNH 2 , I — CH 2 — CH 2 — CH 2 — Br (d) NaNH 2 , I — CH 2 — CH 2 — CH 2 — I 14. H — C ºº C — Ph I2 Product; Product obtained in this reaction is : H–N O (a) Ph — C == CH — I (b) Ph — CH — CH 2 — I | | I I (c) Ph — C ºº C — I (d) I — C ºº C — H 15. C ºº CH ¾(¾i) N¾aN¾H2,¾NH¾3 ® (A) ¾ ¾Lind¾laHr¾c2at¾aly¾st ® (B) ; Product (B) is : (a) (ii)CH3Br C ºº C — 3 CH H CH3 HH (b) C CH C == C (c) CH C H (d) H CH3 16. Which of the following alkyne on treatment with H 2(2 mole)/ Pt gives an optically inactive compound ? (a) 3-Methyl-1-pentyne (b) 4-Methyl-1-hexyne (c) 3-Methyl-1-heptyne (d) None of the above 17. CaC 2 ¾¾H2¾O ® ( A) ¾¾Red¾hot¾Cu¾tu¾be ® (B) , Product (B) of the reaction is : (Calcium carbide) (a) Toluene (b) Ethyl-benzene (c) Benzene (d) Butyne 18. What is the final product, C, of the following reaction sequence ? H ¾¾1.¾Na¾NH2¾¾® A 2. CH3CH2Br A ¾¾Na,¾NH¾3(li¾q¾.)® B Br B ¾¾Br¾2¾® C Br Br (a) CH 2Cl 2 Br Br Br (b) (c) (d) NH2 Br https://t.me/studyzee

261 19. Compound (X) 5H2 CH2 — CH2 — CH2 — CH3 Pt Precipitate AgNO3 O OO OO O || || || || || CHO O3 Me2S H — C — CH2 — CH2 — C — C — H + H — C — C — O – H + H — C — O – H + | CHO Compound (X) will be : (a) CH == CH — C ºº CH (b) CH — CH2 — C ºº CH (c) CH — CH2 — C ºº CH (d) C == CH — C ºº CH 20. Choose the sequence of steps that describes the best synthesis of 1-butene from ethanol : (a) (1) NaC ºº CH ; (2) H 2, Lindlar Pd (b) (1) NaC ºº CH ; (2) Na, NH 3 (c) (1) HBr, heat ; (2) NaC ºº CH ; (3) H 2, Lindlar Pd (d) (1) HBr, heat ; (2) KOC(CH 3)3 , DMSO ; (3) NaC ºº CH ; (4) H 2, Lindlar catalyst 21. Which alkyne yields butanoic acid (CH 3CH 2CH 2CO 2H) as the only organic product on treatment with ozone followed by the hydrolysis ? (a) 1-Butyne (b) 4-Octyne (c) 1-Pentyne (d) 2-Hexyne 22. (A) ¾¾2PH¾t2 ® CH2 — CH2 — CH2 O (c) 9 Carlina oxide Unit of unsaturation in compound (A) ? (a) 7 (b) 8 (d) 10 O 23. O ¾¾H3O¾Å ® ( A) ¾¾NaO¾H ® (B) ¾K¾olb¾e e¾lect¾rol¾ysis® (C) ProdOuct (C) of above reaction is: (a) H 2C == CH 2 (b) CH 3 — C ºº C — CH 3 (c) HC ºº CH (d) CH 3 — CH == CH — CH 3 24. To convert 1-butyne to 1-D-butanal, one would carry out the following steps : (I) Sodium amide, then D 2O (II) Disiamy lborane, then hydrogen peroxide/sodium hydroxide (III) The transformation can not be carried out with the indicated reagents. (a) I, followed by II (b) II, followed by I (c) III (d) II https://t.me/studyzee

262 25. An unknown compound ( A) has a molecular formula C 4H 6 . When (A) is treated with excess of Br2 a new substance (B) with formula C 4H 6Br4 is formed. (A) forms a white ppt. with ammonical silver nitrate solution. ( A) may be : (a) But-1-yne (b) But-2-yne (c) But-1-ene (d) But-2-ene 26. One mole of 1,2-dibromopropane on treatment with X moles of NaNH 2 followed by treatment with ethyl bromide gave a pentyne. The value of X is : (a) One (b) Two (c) Three (d) Four C|H3 ¾¾exce¾ss H¾¾Br ® 27. CH3 – CH – C ºº CH The product of the above reaction is : C|H3 Br Br C|H3 Br | | | (a) CH3 – CH – CH – CH2 (b) CH3 – CH – C = CH2 (c) C|H3 Br (d) C|H3 Br | | CH3 – CH – C – CH3 CH3 – CH – CH2 – CH | | Br Br 28. CH 3 — C ºº C — CH 3 ¾C¾old¾KM¾nO¾4 ®( A) Product (A) is: OO OO (a) CH3—CH2—C—C—H (b) CH3—C—C—CH3 OH OH (c) CH3—CH—CH—CH3 (d) O == CH — CH 2 — CH 2CH == O 29. In which reaction last product is Ph — C ºº CH ? Br | ¾¾3¾Na¾NH¾2 ¾® ¾¾NH4¾¾Cl ® (a) C 6H 5 —C — CH 3 Mineral oil, heat | Br (b) C 6H 5CH == CH 2 ¾C¾BC¾rl24® ¾¾Min¾e3rNaa¾l NoiHl¾,2he¾at ® ¾¾NH4¾¾Cl ® O || (c) C 6H 5 — C — CH 3 ¾¾PC¾l5 ® ¾¾Min¾e3rNaa¾l NoiHl¾,2he¾at ® ¾¾NH4¾¾Cl ® (d) All https://t.me/studyzee

263 30. Predict the product of the following reaction sequence. ethyne ¾¾¾¾(1¾) e¾xces¾s N¾aNH¾2 ¾¾¾® (2) excess I—CH2 —(CH2 )2 —CH3 (3) Hr (a) 6-iodo-1-hexyne (b) 1-hexyne (c) 5-decyne (d) 1-iodo-1-hexene 31. The best sequence of reactions to prepare 2-heptanone is (a) propyne ¾¾NaN¾H¾2 ® X ¾¾n-C¾4H¾9¾Br ® Y ¾¾H2O¾, H¾g¾2+ ® H2SO 4 (b) ethyne ¾¾NaN¾H¾2 ® X ¾¾n-C¾5H¾12¾Br ® Y ¾¾H2O¾, H¾g¾2+ ® H2SO 4 (c) 1 - hexyne ¾¾NaN¾H¾2 ® X ¾C¾H2¾Br ® Y ¾¾H2O¾. H¾g¾2+ ® H2SO 4 (d) 1 - pentyne ¾¾NaN¾H¾2 ® X ¾C¾2H¾5¾Br ® Y ¾¾H2O¾, H¾g¾2+ ® H2SO 4 32. The major product of the reaction of 2-butene with cold alkaline KMnO 4 , is (a) O (b) O (d) OH O (c) OH 1. (b) 2. (b) ANSWERS — LEVEL 1 6. (d) 7. (c) 8. (c) 9. (b) 10. (d) 14. (c) 15. (c) 16. (a) 17. (c) 18. (a) 3. (b) 4. (b) 5. (b) 22. (c) 23. (c) 24. (c) 25. (a) 26. (c) 11. (b) 12. (d) 13. (c) 30. (c) 31. (b) 32. (d) 19. (a) 20. (c) 21. (b) 27. (c) 28. (b) 29. (d) https://t.me/studyzee

264 5A ALKYL HALIDES Substitution Reactions (SN1 , S 2 , SNi ) N Level - 1 1. Which of the following is not expected to be intermediate of the following reaction ? OH I H2O + + O+H2 + (a) (b) (c) (d) 2. Br CH3 + NaI ¾A¾ce¾ton¾e ® product; SN2 product of the reaction is : H H CH3 CH2 – CH3 https://t.me/studyzee

265 I CH3 H CH3 I CH3 I CH3 (a) H H (b) H I (c) H (d) H CH3 CH3 CH3 CH3 CH3 H CH2 – CH3 CH2 – CH3 CH2 – CH3 CH2 – CH3 3. Rate of SN2 will be negligible in : Br Br Br Br (a) (b) (c) (d) 4. What is the major product obtained in the following reaction ? CH2–Br ¾¾NH¾3 ® product EtOH Br CH2–NH2 CH2–Br CH2–NH2 CH2–NH2 (a) (b) (c) (d) Br NH2 NH2 CH3 | 5. Cl - CH 2 -C - CH 2 - CH 2 – Cl + I- ¾D¾M¾F ® product; Major product of this reaction is: | CH3 CH3 CH3 | | (a) I - CH 2 - C - CH 2 - CH 2 – Cl (b) Cl - CH 2 - C - CH 2 - CH 2 - I | | CH3 CH3 CH3 CH3 | | (c) H 2C = C - CH 2 - CH 2 = Cl (d) Cl - CH 2 - C - CH 2 = CH 2 | CH3 6. Which of the following expressions is representative of the rate law for a SN2 reaction ? (a) Rate = k [electrophile] (b) Rate = k [electrophile] [nucleophile] (c) Rate = k [nucleophile] 2 (d) Rate = k[electrophile]2 7. H F+ NaI (1 mole) ¾A¾ce¾ton¾e ® ( A) ; Major product of this reaction is : Br H (major) (a) H F (b) I F (c) H I (d) H H I HH H Br H Br I https://t.me/studyzee

266 8. Which of the following alkyl halide undergo rearrangement in SN1 reaction ? CH 3 Cl I | (a) CH 3 – C – CH– CH 3(b) (c) (d) All of these || CH3 CH 3 I 9. Arrange the following three chlorides in decreasing order towards SN1 reactivity. (1) Cl (2) (3) Cl Cl (a) 1 > 2 > 3 (c) 2 > 1 > 3 (b) 2 > 3 > 1 (d) 3 > 2 > 1 10. Which compound undergoes nucleophilic substitution with NaCN at the fastest rate ? (a) Br (b) Br (c) Br (d) Br 11. Rank the following in order of decreasing rate of solvolysis with aqueous ethanol (fastest ® slowest) CH 3 CH3 Br | | H 2C = C — Br Br CH 3 - CH CH 2CH(CH 3 )2 (1) (2) (3) (a) 2 > 1 > 3 (b) 1 > 2 > 3 (c) 2 > 3 > 1 (4) 1 > 3 > 2 12. The reaction of 4-bromobenzyl chloride with sodium cyanide in ethanol leads to the formation of : (a) 4-bromobenzyl cyanide (b) 4-cyanobenzyl chloride (c) 4-cyanobenzyl cyanide (d) 4-bromo-2-cyanobenzyl chloride 13. Which of the following reactant will not favour nucleophilic substitution reaction ? (a) (b) Ph - Br Br (d) All the above CH3 OH | H (c) CH 3 - C - CH 2 - Br (II) | CH3 Br OH – 14. H (I) https://t.me/studyzee

267 Conversion of I to II : (a) takes place by SN1 (b) takes place by SN2 (c) takes place both by SN1 and SN2 (d) does not take place 15. Which is the correct reaction coordinate diagram for the following solvolysis reaction ? CH3 H2O CH3 OH Br OH CH3 ? (b) (a) Reaction Coordinate Reaction Coordinate (c) Reaction Coordinate (d) 16. Reaction Coordinate (a) 14C labelled OTs ¾R¾CO¾2¾H ® product; Product of this reaction is : no label OCOR OCOR (b) (c) both (a) and (b) (d) None of these I CH3 17. ¾N¾B¾S ® (A) ¾C¾H3¾SN¾a ® (B) , Product (B) is : https://t.me/studyzee

268 CH2–S–CH3 I S–CH3 I (b) (a) S–CH3 (d) None of these CH2–Br (c) 18. Which of the following represents the correct graph for SN2 reaction ? log (rate) (a) CH3 – Br CH3 – CH2– Br CH3 – CH– Br CH | | CH3 CH3 – C – Br | CH3 log( rate) (b) CH3 – Br Et – Br i – Pr – Br t – Bu – Br log (rate) (c) CH3 – Br Et – Br i – Pr – Br t – Bu – Br (isopropyl) https://t.me/studyzee

269 log (rate) (d) CH3 – Br Et – Br i – Pr – Br t – Bu – Br 19. Which of the following graph represents correct graph for SN1 reaction : log (rate) (a) CH3 – Br CH3 – CH3– Br CH3 – CH– Br C|H3 | CH3 CH3 – C – Br | CH3 log (rate) (b) CH3 – Br Et – Br i – Pr – Br t – Bu – Br log (rate) (c) CH3 – Br Et – Br i – Pr – Br t – Bu – Br https://t.me/studyzee

270 log (rate) (d) CH3 – Br Et – Br i – Pr – Br t – Bu – Br 20. Which of the following is most reactive toward SN2 reaction ? Cl Cl Cl Cl (a) (b) (c) (d) CH3 Cl NO2 21. Among the given pairs, in which pair first compound reacts faster than second compound in SN1 reaction ? (a) CH 3 - CH 2 - CH 2 - CH 2 - Br or CH 3 - CH 2 CH CH - - 3 | CH3 Br CH 3 | | (b) CH 3 - C - CH 2 - CH 2 or CH 3 - CH- CH - CH 3 || Br Br Br Br (c) or CH3 CH3 | | (d) CH 3 - C - CH 3 or CH 3 - C - CH 3 | | Br I 22. What is the major product of the following reaction ? H 2C = CH - CH 2 - OH ¾eH¾xcB¾erss® Product Br (b) H 2C = CH - CH 2 - Br OH | | (a) CH 3 - CH - CH 2 - Br Br (d) CH 3 - CH - CH 2 - OH | (c) CH 3 - CH - CH 2 - OH https://t.me/studyzee

271 23. S N1 and SN2 products are same with (excluding stereoisomer) : Cl (a) (b) Cl (c) (d) Ph - CH - CH - CH 3 Cl | | CH3 Cl 24. Consider the nucleophilic attacks given below. Select in each pair that shows the greater SN2 reaction rate. O (A) Br + ¯CN or O CH3+ ¯CN (I) (II) (B) H 3C - Br + - SH or H 3C - Br + CH 3SH (III) (IV) (C) Br + Cl - or Br + I- in DMSO (V) (VI) (D) Br + Cl - or Br + I- in methanol (VII) (VIII) ABC D ABC D (a) (I) ; (IV) ; (VI) ; (VIII) (b) (II) ; (III) ; (V) ; (VIII) (c) (I) ; (III) ; (V) ; (VIII) (d) (I) ; (III) ; (V) ; (VII) 25. Which of the two stereoisomers of 4-t-butylcyclohexyl iodide (127 I- ) will undergo SN2 substitution with 128 I- faster, and why ? H H I127 H H I127 H (A) (B) H (a) A will react faster because it is the more stable of the two isomers (b) A will react faster because it will yield a more stable product, and the transition state for both reactions is of the same energy (c) A will react faster because the approach of 128 I- can depart unhindered. https://t.me/studyzee

272 (d) B will react faster because it is less stable than A, and the transition state for both reactions is of the same energy 26. (Z)-2-Butene reacts with Br2 H 2O. The resulting bromohydrin when treated with methoxide in thme estthearneoolcheumndicearlgoceosnseaqnueinnctreasmoofletchuelarreaSctNio2 n reaction. Taking into consideration mechanism involved, choose the final product(s) of these transformations. O OO (I) H CH3 (II) H3C H (III) H H H3C H H CH3 H3C CH3 (a) (I) only (b) (II) only (c) (III) only (d) Equal amounts of (I) and (II) 27. Rank the following species in order of decreasing nucleophilicity in a polar protic solvent (most ® least nucleophilic) : CH 3CH 2CH 2O - CH 3CH 2CH 2S- O (1) (2) || CH 3CH 2 C - O – (3) (a) 3 > 1 > 2 (b) 2 > 3 > 1 (c) 1 > 3 > 2 (d) 2 > 1 > 3 28. Identify products of the given reactions : OTs Reaction-1 ¾C¾H3¾CO¾2N¾a ® Product CH 3CO 2H NMe2 Reaction-2 OTs ¾C¾H3¾CO¾2N¾a ® Product CH 3CO 2H NMe2 O CH3 O CH3 (a) O ; O + enantiomer NMe2 NMe2 O CH3 O CH3 (b) O + enantiomer ; O NMe2 NMe2 O CH3 (c) O single product is obtained in both the reactions NMe2 O CH3 (d) O single product obtained in both the reactions NMe2 https://t.me/studyzee

273 Alog(rate) B 29. CH3–X Me–CH2–X Me2CH–X Me3CH–X Which of the following is true about given graphs A and B ? (a) A ® SN1 B ® SN2 (b) A ® SN2 , B ® SN1 (c) A & B ® E 1 (d) A & B ® E 2 30. In each of the following groups, which is the strongest (best) nucleophile ? (I) (1) H 3C - O - (2) O¯ (3) H 3 C - S- in CH3OH (II) (1) OH - (2) H 2O (3) NH - in DMF O¯ 2 (III) (1) (2) O¯ (3) CH 3O - in DMSO (a) I,3 ; II,3 ; III,2 (b) I,2 ; II,1 ; III,3 (c) I,1; II,2 ; III,1 (d) I,3 ; II,1 ; III,3 O 31. S – (CH2)4 – CH2 – Cl ¾¾¾N¾aNH¾2 ¾¾® ( A) ; Product ( A) is : (a) (c) dimethoxy ethane (Major) O OO || S - (CH 2 ) 3 - CH = CH 2 (b) S || O O O || S - (CH 2 ) 4 - CH 2 - NH 2 (d) None of these || O 32. Which of the following reaction is an elimination reaction ? H H Br KI ¾¾® (a) OH ¾H¾2S¾O4® + H (b) + IBr + KBr H H H Br (c) Br ¾Na¾OC¾H3® OCH3 (d) both (a) and (b) https://t.me/studyzee

274 33. ¾¾C¾H3O¾Na¾¾® Product O CH2 – Cl CH3OH(SN1 ) Which of the following products can be obtained from above reaction ? (a) O CH2 – OCH3(b) CH3O O OCH3 (d) All of these (c) O CH3 34. What is the principal product of the following reaction ? CH3 H Br H H + NaN 3 ¾® Product H Cl H CH3 N3 CH3 N3 CH3 H CH3 (a) H CH3 (b) H H (c) H H (d) H N3 H H N3 H H H Cl Cl H H Cl Cl H CH3 CH3 CH3 CH3 35. What would be the effect of increasing solvent polarity on the rate of each of the following reactions ? (Nu = neutral nucleophile) Å (A) Nu + R - L ¾® Nu- R + L- (a) increases (b) decreases (c) constant (d) can not be predicted (B) R - LÅ ¾® R Å + : L (a) increases (b) decreases (c) constant (d) cannot predict 36. Which of the following is most reactive toward SN2 reaction ? (a) CH 2 = CH - CH 2 - Cl (b) Ph - CH 2 - Cl (c) Me – O Cl (d) Ph - C- CH 2 - Cl || O 37. 4-chloro-1-butanol + NaOH ¾® (B) Product (B) of the above reaction is : (a) O (b) (c) O CH3 CH2 – CH3 O (d) O https://t.me/studyzee

275 38. In the given pairs of alkyl-halide, in which pair the first compound is more reactive than second compound toward SN2 reaction ? (a) (CH 3 )2 CHBr or CH 3 - CH 2 - CH 2 - Br (b) CH 3 - CH 2 - CH 2 - Br or CH 3 - CH 2 - CH 2 - I (c) Ph - Br or CH 3 - CH 2 - CH 2 - Br (d) CH 2 = CH - CH 2 - Cl or H 2C = CH - Cl 39. In the given pair of reaction in which pair the second reaction is more reactive than first toward SN2 reaction ? - CH 2 -O– ¾® Et - O - Et (or) (a) CH 3 - CH 2 - Cl + CH 3 CH 2 - CH 2 - Cl + CH 3 - CH 2 - OH ¾® Et - O - Et (b) CH 3 - CH 2 - Cl + EtO - ¾® Et - O - Et (or) CH 3 - CH 2 - Cl + EtS– ¾® CH 3 - CH 2 - S - Et (c) Et - Cl + CH 3O - ¾® Et -O - CH 3 (or) (1m) ( 2m) Et - Cl + CH 3O - ¾® Et - O - CH 3 (2m) (1m) Å (d) Et - Br + Ph 3P ¾® Et - PPh 3 (or) Å Et - Br + Ph 3N ¾® E + - NPh 3 40. Among the following pair of reactions in which pair the second reaction is more reactive than first in SN1 reaction ? (or) Me 3CBr + H 2O ¾® Me 3COH (a) Me 3CCl + H 2O ¾® Me 3COH (b) Me 3CCl + CH 3OH ¾® Me 3C — OCH 3 (or) Me3C—Cl + H2O Me3C—OH (c) Me 3CCl+ H 2O ¾® (or) Me 3CCl+ H 2O (1M) (2M) (d) All of these 41. Which is a true statement concerning the transition state of an SN2 reaction ? (a) Closely resembles a carbocation intermediate (b) The electrophile is responsible for the reaction (c) Lower is energy than the starting materials (d) Involves both the nucleophile and electrophile 42. Increasing the concentration of a nucleophile in a typical SN 2 reaction by a factor of 10 will cause the reaction rate to : (a) increase by a factor of 10 (b) increase by a factor of 10 2 (c) decrease by a factor of 10 (d) remain about the same 43. Decreasing the concentration of an electrophile in a typical SN2 reaction by a factor of 3 will cause the reaction ratio to : (a) increase by a factor of 3 (b) increase by a factor of 3 2 (c) decrease by a factor of 3 (d) remain about the same https://t.me/studyzee

276 44. tInhcerceoansicnegnttrhaeticoonncoefnthtreatniouncleoof pahnileelebcytraopfahcilteorinofa3tywpiicllaclhSaNn2greetahcetiorenabctyioanfarcattoertoof:3 and (a) increase by a factor of 6 (b) increase by a factor of 9 (c) decrease by a factor of 3 (d) remain about the same 45. Consider the following reaction and select the best choice that represents the reaction. CH3 H ¾N¾až-S¾CH¾2CH¾¾3 ® Product Br CH3 CH3 CH3 (a) H (b) H SCH2CH3 SCH2CH3 CH3 CH3 CH3 (c) SCH2CH3 (d) S – CH2CH3 H H I Me H 46. Et D ¾K¾S¾H ® Product; Identify the product. H H H SH SH Me H Me H HS Me H Me (a) Et D (b) Et D (c) Et D (d) Et D H SH H H 47. The reaction , H Cl H OH + SO2 + HCl + SOCl2 proceeds by the........... mechanism. (a) SNi (b) SN2 (c) SE2 (d) SN1 48. Consider the following anions. O O O– O C6H5 – S – O– CH3 – C – O– CF3 – S – O– (III) O (IV ) O (II ) (I ) When attached to sp 3-hybridized carbon, their leaving group ability in nucleophilic substitution reaction decreases in the order : (a) I > II > III > IV (b) I > II > IV > III (c) IV > I > II > III (d) IV > III > II > I https://t.me/studyzee

277 H Ph CH3 sr 49. Cl Ph H ¾P¾h S¾N¾a ® Principal organic product of the reaction will be : SN2 Ph Ph CH3 H H H CH3 (a) PhS (b) H SPh Ph Ph Ph Ph Ph CH3 H CH3 (c) H Cl (d) H Ph Ph Ph 50. Reaction of R-2-butanol with p-toluenesulphonyl chloride in pyridine followed by reaction with LiBr gives: (a) R-2-butyl bromide (b) S-2-butyl tosylate (c) R-2-butyl tosylate (d) S-2-butyl bromide 51. The compound which undergoes SN1 reaction most rapidly is : (a) Br (b) Br (c) CH2Br (d) Br 52. Addition of KI accelerates the hydrolysis of primary alkyl halides because : (a) KI is soluble in organic solvents (b) the iodide ion is a weak base and a poor leaving group (c) the iodide ion is a strong base (d) the iodide ion is a powerful nucleophile as well as a good leaving group 53. Which of the following phrases are not correctly associated with SN1 reaction ? (1) Rearrangement is possible (2) Rate is affected by polarity of solvent (3) The strength of the nucleophile is important in determining rate (4) The reactivity series is tertiary > secondary > primary (5) Proceeds with complete inversion of configuration (a) 3, 5 (b) 5 only (c) 2, 3, 5 (d) 3 only https://t.me/studyzee

278 CH3 54. ¾S¾O2¾C¾l2 ® (A) ¾N¾B¾S ® (B) ¾K¾S¾H ® (C) , Product (C) is : hv SH SH Br Br (a) Br (b) Cl (c) SH (d) 55. Energy profile diagram for an exothermic reaction, A ¾1® B ¾2® C ¾3® D, is given below. 1 23 P.E. BC A D Progress of the reaction The rate determining step of the reaction is : (a) A ¾® B (b) B ¾® C (c) C ¾® D (d) can not predict CH3 56. ¾N¾BS® ( A) Major Major product (A) is : Br Br (d) Br (a) (b) (c) Br 57. Cl ¾L¾iBr¾/D¾MS¾O ® Major product (X) Cl S N2conditions The product X is : https://t.me/studyzee

279 (a) Br (b) Cl Cl Br (c) Br (d) Cl Br 58. Relative rate of reaction of the following amine with methyl iodide is: (a) A > B > C N N (d) B > A > C N N (C) (A) (B) (c) B > C > A (b) A > C > B H PhCH2O OTs C CH 59. HH C OCH3 ¾ ¾Dim¾et¾hyNla¾sIulf¾oxi¾d¾e ® OCH3 Major product which you expect in the above reaction is : HH OTs I C CH OCH2Ph C I (a) H H C H C OCH3 (b) C OCH3 HH OCH3 OCH3 I H OCH2Ph C H OCH2Ph C OTs C H C I (c) H H C OCH3 (d) H H CH OCH3 OCH3 HS H HS NaOH in (A) + 60. aqueous EtOH (major) H Cl C6H10S H Major product of the above reaction is : HS SH S (a) (b) S (c) (d) H OH https://t.me/studyzee

280 H 61. CH3 — C — C14 — CH3 ¾¾® Major product of the reaction is: D CH3 OTs Ph (a) CH3 14 Ph 14 C C (b) CH3 — C — CH CH2 CH3 CH3 CH3 (c) CH3 C 14 Ph CH3 C Ph (d) C C CH3 1C4H3 CH3 CH3 62. The decreasing order of reactivity of the compounds given below towards solvolysis under identical conditions is : Cl Cl || CH3 – C – CH3 CH3 – C – CH3 Cl | CH3 – C – CH3 H3C (I) (II) (III) (a) II > III > I (b) I > II > III (c) III > II > I (d) II > I > III OH 1.One Eq. NaOH 63. ¾¾¾¾¾¾¾¾® (A); Product (A) is : OH 2. MeBr OMe OH OH (a) OH (b) OMe (c) (d) None of these 64. ( R )-2-octyl tosylate is solvolyzed in water under ideal SN1 conditions. The product(s) will be: (a) R-2-octanol and S-2-octanol in a 1 : 1 ratio (b) R-2-octanol and S-2-octanol in a 1.5 : 1 ratio (c) R-2-octanol only (d) S-2-octanol only https://t.me/studyzee

281 65. From each of the following pairs select the compound that will react faster with sodium iodide in acetone : Pair-A: (1) 2 - Chloropropane (2) 2 - Bromopropane Pair-B: (3) 1 - Bromobutane (4) 2 - Bromobutane (a) 1,3 (b) 1, 4 (c) 2,3 (d) 2, 4 66. Among the given halides, which one will give same product in both SN1 and SN2 reactions. C|H3 CH3 (I) CH 3 - CH - CH 2 - CH - CH 3 (II) Cl | Br Cl (III) (IV) CH 3 - CH - Br (a) (III) only | Et (b) (I) & (II) (c) (III) & (IV) (d) (I), (III) & (IV) 67. Product(s) formed during this reaction is/are : CH2 – C*H2 – OTs ¾A¾cO¾N¾a ® Product ? [ C* = isotopic carbon] AcOH C*H2 – CH2 – OAc CH2 – C*H2 – OAc (a) (b) CH2 – C*H2 – OTs (d) Both (a) & (b) (c) OAc 68. Anisole ¾e¾xce¾ss ¾HI (¾con¾c¾.) ® Product reflux (a) I + CH3I (b) I + CH3OH (c) OH + CH3I (d) OH + CH3CH2I 69. Which of the following compounds would react faster with NaCN in an SN2 reaction ? OMe (a) (b) OTs (c) MeO (d) OTs https://t.me/studyzee

282 70. HC ºº CNa + Cl – CH 2 – CH 2 – CH 2 – I ¾® (A); Major product (A) is : (a) H – C º C – CH 2 – CH 2 – CH 2 – I (b) CH 2 = CH – CH 2 – I (c) H – C º C – CH 2 – CH 2 – CH 2 – Cl (d) CH 2 = CH – CH 2 – Cl 71. What is the major product obtained in the following reaction ? SNa + CH3 — Br Et2O Product. (a) (b) Br (c) S (d) CH3 Br CH3 + OH - ¾S¾N¾2 ® A; The product A is : CH3 72. H H H CH3 H H (b) HO HO (a) H (c) Both (a) and (b) are correct (d) None is correct 73. Me 2C = CH – CH 2 – CH 2 – Cl ¾¾H¾2O¾® ( X ); Major product of the reaction is : CaCO 3 OH | (a) Me – C – CH 2 – CH 2 – CH 2 (b) Me 2C = CH – CH 2 – CH 2 – OH | Me OH (c) Me 2C = CH – CH – CH 2 – OH (d) CMe2 | OH OH OH 74. ¾H¾B¾r ®( A) , ¾H¾B¾r ®(B) D D CH2OH OCH3 Product (A) and (B) respectively are : OH OH OH OH (a) and (b) and CH2Br Br CH2Br OH https://t.me/studyzee

OH Br Br 283 (c) and (d) and Br CH2Br OH CH2OH OCH3 75. Relative rate of reaction with H 2O. H ONS H ONS H ONS CH3 CH3 (i) (ii) CH3 (iii) çæ O ÷ö || NO 2 ÷ ç —ONS == —O — S ç || ÷÷ ç O ø è (a) (i) > (ii) > (iii) (b) (ii) > (i) > (iii) (d) (iii) > (i) > (ii) (c) (iii) > (ii )> (i) OO 76. ¾2¾eq¾. K¾NH¾2 ® ¾n¾—¾C4¾H9 ¾— B¾r ® (P) ; NH 3 ( l ) then H3OÅ End product (P) of the above reaction is : OO OO (a) (b) OO OO (c) (d) 77. Which of the following statements is correct regarding the rate of hydrolysis of the compounds (A) and (B) by SN1 reaction ? Br O Br A B https://t.me/studyzee

284 (a) A reacts faster than B (b) B reacts faster than A (c) Both A and B reacts at the same rate (d) Neither A nor B reacts 78. What are reactant X and product Y in the following sequence of reactions ? H3C O H3C O CH3 NaN3 Product Y Reactant X H OS SCl HO Ethanol-water O Pyridine Reactant X Product Y N3 (a) H3C OH H H HH (b) H3C OH H H HH N3 (c) H3C H H H OH H N3 (d) H3C H N3 H OH H H 79. Transition state of given SN2 is : CH2—Br R-O– CH2—O—R SN2 reaction ds ++ d (+) ++ OR OR H (a) H H (b) drBr H Br d (+) https://t.me/studyzee

285 dr ++ d (–) ++ OR OR H H (c) (d) H H dsBr Br d (–) 80. C 6H13Br + OH - ¾® C 6H13OH + Br - is an example of: (a) Nucleophilic addition (b) Nucleophilic substitution (c) Electrophilic addition (d) Electrophilic substitution (e) Free radical substitution 81. Transition state 2 is structurally most likely as : T.S.2 T.S.3 intermediate 2 T.S.1 E intermediate 1 reactant product (a) intermediate 1 (b) transition state 3 (c) intermediate 2 (d) product O CH2 82. O O x = Number of aromatic compound obtained when above compound undergo complete acidic hydrolysis. (a) 1 (b) 2 (c) 3 (d) 4 83. SN 1 and SN 2 reactions are (a) Both stereospecific (b) Both stereoselective (c) Stereoselective and stereospecific respectively (d) Stereospecific and stereoselective respectively https://t.me/studyzee

286 84. Most reactive compound toward SN1 is : CH2—I CH2—I CH2—I CH2—I (d) (a) (b) (c) CH CH3CH2 C 1. NaNH2(2 eq.) 85. ¾2¾.C¾H3C¾H2¾—¾I ¾® Product ( X ) is : 3. CH3 — I 4. H2/ Pd-BaSO4 OH CH3CH2 (a) (b) CH3 CH2—O—CH3 OCH3 CH3 (c) (d) CH2—OCH2CH3 O—CH2CH3 86. Following reaction is an example of : O + R2NH (a) SN 2 Reaction (b) SN1 Reaction (c) Electrophilic Addition (d) SN – NGP 87. The major product of the following reaction : OH | HBr [x] Br H (c) (d) OH (a) | (b) | Br 88. Choose the suitable option for the correct mechanism for the following reactions. (I) + CH3O CH3OH (II) + CH3OH Br high Br concentration https://t.me/studyzee

287 (a) SN1, SN1 (b) SN1, SN 2 (c) SN 2, SN1 (d) SN 2, SN 2 O O 89. H+ Reaction 1 HO O OMe O O OO O N3– O Reaction 2 Br N3 Types of mechanism followed by reaction 1 and reaction 2 respectively. (a) SN1, SN1 (b) SN 2, SN 2 (c) SN1, SN 2 (d) SN 2, SN1 OTs OTs 90. H2S Product KOH Product of above reaction will be : OTs SH OTs SH (a) (b) (c) (d) S S 1. (a) 2. (b) ANSWERS — LEVEL 1 6. (b) 7. (b) 8. (d) 9. (b) 10. (a) 14. (d) 15. (b) 16. (c) 17. (a) 18. (a) 3. (c ) 4. (a) 5. (b) 22. (a) 23. (c) 24. (c) 25. (d) 26. (d) 11. (c) 12. (a) 13. (d) 30. (d) 31. (b) 32. (d) 33. (d) 34. (c) 19. (c) 20. (d) 21. (b) 37. (b) 38. (d) 39. (b) 40. (d) 41. (d) 27. (d) 28. (a) 29. (a) 45. (c) 46. (d) 47. (a) 48. (b) 49. (b) 35. A(a) 35. B(b) 36. (d) 53. (a) 54. (b) 55. (a) 56. (a) 57. (b) 42. (a) 43. (c) 44. (b) 61. (c) 62. (d) 63. (a) 64. (b) 65. (c) 50. (d) 51. (b) 52. (d) 69. (d) 70. (c) 71. (c) 72. (b) 73. (d) 58. (c) 59. (c) 60. (b) 77. (b) 78. (b) 79. (d) 80. (b) 81. (c) 66. (d) 67. (d) 68. (c) 74. (b) 75. (c) 76. (d) 85. (b) 86. (a) 87. (c) 88. (c) 89. (c) 82. (b) 83. (b,c) 84. (d) 90. (b) https://t.me/studyzee

288 Level - 2 1. Statement-1 : Nucleophilicity order in polar-protic solvent is I- < Br - < Cl - < F - Statement-2 : Due to bigger size of I- it is less solvated in polar-protic solvent. (a) Statement-1 is true, statement-2 is true and statement-2 is correct explanation for statement-1. (b) Statement-1 is true, statement-2 is true and statement-2 is NOT the correct explanation for statement-1. (c) Statement-1 is true, statement-2 is false. (d) Statement-1 is false, statement-2 is true. 2. Statement - 1 : CH 3 - CH 2 - Cl + NaI ¾A¾ce¾to¾ne® CH 3 - CH 2 - I + NaCl ¯ Statement- 2 : Acetone is polar-protic solvent and solubility order of sodium halides decreases dramatically in order NaI > NaBr > NaCl. The last being virtually insoluble in this solvent and a 1º and 2º chloro alkane in acetone is completely driven to the side of Iodoalkane by the precipitation reaction. (a) Statement-1 is true, Statement-2 is true and Statement-2 is correct explanation for statement-1. (b) Statement-1 is true, Statement-2 is true and Statement-2 is Not the correct explanation for statement-1. (c) Statement-1 is true, Statement-2 is false. (d) Statement-1 is false, Statement-2 is true. 3. Encircle whichever of the following : (a) is the stronger nucleophile (aprotic solvent) : F - or I- (b) is the stronger nucleophile (protic solvent) : F - or I- (c) is the stronger base : F -or I- (d) is the stronger nucleophile (protic solvent) : NH3 or NH 2NH 2 (e) is the better leaving group : CH 3COO - - or CH 3SO 3 4. Encircle whichever of the following : Br | (a) undergoes an SN2 reaction more rapidly, CH 3 - Br or CH 3 - CH - CH 3 Br | (b) undergoes an SN1 reaction more rapidly, CH 3 - Br or CH 3 - CH - CH 3 Ph Ph (c) undergoes an E 2 reaction to give (Z)-1,2-diphenylpropene : H C = C CH3 Ph Ph H Br Br H H CH3 or H CH3 Ph Ph https://t.me/studyzee

(d) reacts with NaI to give (Z)-1,2-diphenylpropene : 289 Ph Ph CH3 H Br H Br or Br CH3 Br CH3 Br C|H3 Ph C–CH2–CH3 Ph Br Br (e) undergoes an SN1 reaction more rapidly, Br or 5. Encircle whichever of the following : CH2–Br or (a) undergoes an SN2 reaction more rapidly : (b) undergoes an E 1 reaction more rapidly : C|H3 CH–CH2–C|H2 Br or (c) undergoes an SN1 reaction more rapidly: Br or (d) undergoes an SN2 reaction more rapidly: Cl Br Cl or Cl Cl (e) undergoes an E 2 reaction more rapidly : or https://t.me/studyzee

290 6. Match the column : Alkyl halide (p) Relative rate Relative rate (q) (SN1 ) (SN2 ) (a) CH 3 – Br (r) 1200 (b) CH 3 - CH 2 – Br 1 (w) (s) 40 CH 3 - CH - Br 1.05 (x) (c) | 11 (y) 16 CH3 CH3 1,200000 (z) 1 | (d) CH 3 - C - Br Column (II) | Type of reaction CH3 (p) SN1 reaction can take place 7. Matrix : (q) SN2 reaction can take place Column (I) Compound (r) SN1 is not possible Cl (s) SN2 is not possible (a) Cl (b) Cl (c) Cl (d) https://t.me/studyzee

8. Encircle whichever of the following : 291 (a) undergoes an SN2 reaction more rapidly, Br or Br (b) undergoes an SN1 reaction more rapidly, (CH 3 )3 C - Br or (CH 3 )3 C - I Br Br (c) undergoes an SN1 reaction more rapidly, or 9. Reactivity : Circle the reaction that reacts FASTER by SN2 in each pair : (1) Cl ¾N¾aO¾CH¾3 ® (2) I ¾O¾H¾- ® (3) Cl ¾N¾aO¾¾H ® Br ¾N¾aO¾CH¾3 ® I ¾N¾aO¾¾H ® Cl ¾N¾aO¾¾H ® 10. Consider the potential energy diagram given below B D E nergy C A E F Reaction Progress (X) Name the positions A-D (Y) Answer the following questions . (i) Both reaction pathways are : EXOTHERMIC or ENDOTHERMIC (ii) Which step is the rate determining step (RDS) ? B or D (iii) Which product is most stable ? E or F (iv) In accordance with Hammonds postulate, exothermic reactions tend to have (a) early transition states that are reactant - like (b) late transition states that are reactant-like (c) early transition states that are product-like (d) late transition states that are product-like. https://t.me/studyzee

292 11. Select whether the following combinations of reactants will react by substitution (S N1 or SN2 mechanism), elimination (E 1 or E 2 mechanism) A. Br NaI in acetone ¾¾¾¾¾¾® 25°C (a) SN1 (b) SN2 (c) E 1 (d) E 2 B. Cl ¾Na¾OC¾H¾3 in¾m¾eth¾ano®l 50°C (a) SN1 (b) SN2 (c) E 1 (d) E 2 C. N¾aO¾CH¾3 ¾in m¾et¾han®ol Cl 25°C (a) SN1 (b) SN2 (c) E 1 (d) E 2 (c) E 1 (d) E 2 D. (CH 3 )3 C - OH ¾H¾Br¾48¾% i¾n H¾2O® (d) E 2 25°C (a) SN1 (b) SN2 E. (CH 3 )2 CH - Br ¾¾Na¾CN¾in¾eth¾an¾ol ® 25°C (a) SN1 (b) SN2 (c) E 1 HH F. Br ¾¾Na¾CN¾in¾eth¾an¾ol ® 25°C (a) SN1 (b) SN2 (c) E 1 (d) E 2 (d) E 2 G. (CH 3 )2 CHCH 2CH 2 - OH ¾¾HB¾r 4¾8%¾in¾H2¾O ® 50°C (a) SN1 (b) SN2 (c) E 1 https://t.me/studyzee

293 12. Examine the ten structural formulas shown in fig. & select that satisfy each of the following conditions. Write one or more (a through j) in each answer box. CH 3 | (a) Br (b) H 3C — C — Cl (c) CH2 – Br Cl | CH 3 CH2 – Br (d) CH 3 - I (e) (f) CH 3 H2C CH2 — Cl Br | C (g) H 3C — C — CH 2 — Cl (h) | (i) | CH3 CH 3 Cl (j) A. Which compounds give an SN2 substitution reaction on treatment with alcoholic NaSH ? B. Which compounds give an E 2 elimination reaction on treatment with alcoholic KOH ? C. Which compounds do not react under either of the previous reaction conditions ? https://t.me/studyzee

294 13. Select which reaction from the following reaction pairs will occur faster. PART - 1 OH I Reaction A CH3 ¾H¾2¾O ® CH3 DMSO Reaction B I OH H ¾H¾2¾O ® H DMSO Reaction C PART - 2 I Reaction D Cl CH3 CH3 ¾N¾¾aI ® CH2I DMSO CH2Cl ¾N¾¾aI ® DMSO Reaction E PART - 3 Cl Reaction F I H H ¾N¾a¾Cl ® Cl DMSO H I H ¾N¾a¾Cl ® EtOH Reaction G PART - 4 N3 Reaction H I H H ¾N¾aN¾3 ® N3 DMSO H Br H ¾N¾aN¾3 ® DMSO https://t.me/studyzee

295 PART - 5 CH2 — I CH2 — Cl Reaction I ¾N¾¾aI ® acetone I Br Reaction J ¾N¾¾aI ® acetone CH3 CH3 14. Tick your answer in the given box. Alkyl Halide 2-D Structure Expect SN2 (a) 1-Bromobutane (at a reasonable rate) (b) 1- Chlorobutane Br (c) 2-Bromobutane Cl Yes (d) 2-Chlorobutane No (e) 2-Chloro-2-methyl propane Br Yes Cl No Yes Cl No Yes No Yes No https://t.me/studyzee

296 Br Yes (f) Bromocyclohexane Br (g) Bromobenzene CH2 – Br No (h) Benzyl bromide Br Yes (i) 1-Bromo-2,2-dimethyl Br No propane Br Yes (j) Bicyclo compound No Yes (k) 1-bromotriptycene No Yes No Yes No https://t.me/studyzee

15. Match the column 297 Column-II Column-I (p) It will undergo Nucleophilic Substitution Cl reaction (a) (b) (q) It will undergo E 2 reaction CH2—Cl (r) It will undergo E1 reaction (s) It will undergo SN 2 reaction CH3 (c) C—Cl CH3 F (d) NO2 (t) It will undergo SN1 reaction 16. O O—Et ¾ ¾xH¾I ® O O—Et How many (x) moles of HI consumed? https://t.me/studyzee

298 Column (I) Column (II) 17. Cl ¾H¾2O® (p) S N1 (q) S N 2 (a) Ph (r) Carbocation is intermediate (s) Carbanion is intermediate (b) Cl sr (c) (d) ¾P¾h—¾S¾Na® 18. F (a) ¾¾KOD¾H ® NO ¾¾CBCr¾l24 ® Column (I) Column (II) (Reaction sequence) (Reagent required) Os ¾® OEt (p) EtOs (b) Br ¾® (q) EtBr OEt (r) r (c) ¾® EtOH/H (d) Et — Cl ¾® (s) Et–Cl/Na ether https://t.me/studyzee

299 19. Choose the one compound within each set that meets the indicated criterion : Column (I) Column (II) (a) The compound that reacts with alcoholic F KOH to liberate Halide ion through substitution reaction. (p) O2N CH3 (b) The compound that cannot be prepared by a Williamson ether synthesis. (q) OC2H5 (c) The compound that gives an acidic solution O when allowed to stand in aqueous ethanol. (r) F (d) The ether that cleaves more rapidly in HI. (s) Br —C—CH3 CH3 20. Comprehension The first demonstration of the stereochemistry of the SN2 reaction was carried out in 1935 by Prof. E.D. Hughes and his colleagues at the University of London. They allowed (R)-2-iodooctane to react with radioactive iodide ion (*I–). CH3CH(CH2)5CH3 + *I– CH3CH(CH2)5CH3 + I– I *I 2-iodooctane 2-iodooctane (radioactive) The rate of substitution (rate constant K s ) was determined by measuring the rate of incorporation of radioactivity into the alkyl halide. The rate of loss of optical activity from the alkyl halide (rate constant K o) was also determined under the same conditions. What ratio K o / K s is predicted for each of the following stereochemical scenarios : A. For inversion reaction : (a) K o = 1 (b) K o < 1 (c) K o > 1 (d) can not be predicted Ks Ks Ks (d) can not be predicted B. For equal amounts of both retention and inversion ? (a) K o = 1 (b) K o < 1 (c) K o > 1 Ks Ks Ks https://t.me/studyzee