HALOGEN DERIVATIVES EXERCISE–I (A) (Choose the correct option. Only one is correct) Q.1 Which one of the following compounds will be most reactive for SN1 reactions: (A) (B) (C) (D) Q.2 The major product in the given reaction: + NH3 (A) (B) (C) (D) All of these Q.3 In the given reaction: CH3CCNa Et2O / the products are: (A) and (B) + (C) (D) Q.4 Consider the following groups: (I) —OAc (II) —OMe (III) —O—SO2—Me (IV) —O—SO2—CF3 The order of leaving power is: (A) I > II > III > IV (B) IV > III > I > II (C) III > II > I > IV (D) II > III > IV > I Q.5 Which one of the following compounds will give enantiomeric pair on treatment with HOH? C2H5 | (A) C6H5 C I | C2H5 CH 3 | (B) CH3 C Br | C2H5 H | (C) C6 H5 C Br | D C2H5 | (D) C2H5 C Br | CH3 Q.6 Arrange the following compounds in order of decreasing rate of hydrolysis for SN1 reaction: (I) CH2–Br (II) H3C CH2–Br (III) CH3–CH2 CH2–Br (IV) CH CH2–Br (A) II > III > IV > I (B) IV > III > II > I (C) III > IV > II > I (D) I > II > III > I Q.7 Which of the following nucleophile will show minimum reactivity towards SN2 reaction: (A) Me3CO (B) MeO (C) (D) Me2CHO Q.8 In the given reaction NaOH [X] HOH 25C (A) (B) (C) Mixture of (A) and (B) (D) Q.9 Rate of SN2 reactions depends on: (A) The nucleophile (B) The carbon skeleton (C) The leaving group (D) All of these Q.10 Consider the given reaction: CH3–CH=CH–CH2–OH HBr [P] SN1' In the given reaction the product [P] is : Br | (A) CH3–CH=CH–CH2–Br (B) CH3 CH CH CH2 Br | (C) CH2=CH–CH=CH2 (D) CH3 CH CH2 CH2 OH Q.11 For the given reaction R1 R1 | | R C X | R 2 HOH R C OH | R 2 Which substrate will give maximum racemisation? CH3 | CH3 | (A) C6H5 C Br | C2H5 (B) CH2 CH C Br | C2H5 (C) (D) Q.12 Consider th following four reactions: (I) (+) C H CH Cl 95%acetone C H CH OH 6 5 | CH3 5% water 6 5 | CH3 (II) (+) C H CH Cl 90%acetone C H CH OH 6 5 | CH3 10% water 6 5 | CH3 (III) (+) C H CH Cl 80%acetone C H CH OH 6 5 | CH3 20% water 6 5 | CH3 (IV) (+) C6H5 CH Cl 100%water C H | 6 5 CH3 CH OH | CH3 Arrange these reactions in decreasing order of greater proportion of inverted product and select correct answer from the codes given below: (A) I > II > III > IV (B) II > I > III > IV (C) III > II > I > IV (D) IV > III > II > I Q.13 Which of the following ester will give always SN2 mechanism in acidic as well as basic conditions? (A) CH3–O–CH3 (B) C6H5–O–CH3 (C) (D) All of these Q.14 In the given reaction: CH3 CH 2 • • •S• CH2 CH2 Br HOH [X] [X] will be: (A) CH CH S C* H CH2 OH (B) CH CH S CH C* H OH (C) 1 : 1 mixture of (A) and (B) (D) 2 : 1 mixture of (A) and (B) Q.15