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SN2 mechanism, rate, stereochemistry, steric effects

28 questions on SN2 mechanism, rate, stereochemistry, steric effects from the Organic Reaction Mechanisms III: Nucleophilic Substitution chapter: 6 NEET level, 12 JEE Main, 10 JEE Advanced. Each one opens with its answer and solution.

Practice this topic All Organic Reaction Mechanisms III: Nucleophilic Substitution topics

In the S_N2 reaction CH3Br + OH- -> CH3OH + Br- the rate law is rate = k[CH3Br][OH-]. If the concentrations of both CH3Br and OH- are doubled at constant temper... NEET level
Optically pure (R)-2-bromooctane reacts with a high concentration of OH- in aqueous acetone purely by the S_N2 pathway. The product is NEET level
Which of the following alkyl bromides reacts fastest with NaI in dry acetone by the S_N2 mechanism? NEET level
In the Finkelstein reaction, CH3CH2CH2Cl is heated with NaI in dry acetone. The main product and the reason the reaction goes to completion are NEET level
The best Williamson synthesis of tert-butyl methyl ether (CH3)3C-O-CH3 uses NEET level
In the Swarts reaction, bromoethane is converted to fluoroethane by heating with NEET level
The reaction CH3I + CH3S- -> CH3SCH3 + I- follows the rate law rate = k[CH3I][CH3S-]. Solution X contains 0.10 M CH3I and 0.10 M CH3S- and has initial rate r. S... JEE Main level
Assertion (A): Neopentyl bromide (CH3)3C-CH2-Br, a primary halide, undergoes SN2 with NaI in acetone much more slowly than isopropyl bromide, a secondary halide... JEE Main level
Each of the following bromides is treated separately with NaI in acetone under identical conditions. Which one reacts fastest by the SN2 pathway? JEE Main level
Consider 1-bromobicyclo[2.2.1]heptane, in which the bromine is on a bridgehead carbon. Select the correct statements. JEE Main level
Allyl bromide CH2=CH-CH2-Br reacts with iodide in acetone considerably faster than 1-bromopropane although both are primary. The best explanation is that in the... JEE Main level
(R)-2-Bromobutane is treated with NaCN in DMSO and the reaction proceeds entirely by SN2. The product is JEE Main level
Hypothetical relative rate constants for SN2 reaction of RBr with iodide in acetone (ethyl bromide = 1.00) are: CH3CH2Br 1.00; CH3CH2CH2Br 0.40; (CH3)2CHCH2Br 0... JEE Main level
Match the named reaction in List I with the transformation in List II. Which combination is correct? List I: P Finkelstein; Q Swarts; R Williamson; S Gabriel. L... JEE Main level
Which of the following alkoxide and alkyl halide pairs give the stated ether in good yield by the Williamson synthesis? JEE Main level
In the Fischer projection of 2-bromobutane, the vertical chain from top to bottom is CH3, the stereocentre C2, then CH2CH3. At C2 the bromine is on the left and... JEE Main level
Each of the following bromides is treated with NaI in dry acetone at 25 degC. Which of them react faster than bromoethane under these conditions? JEE Main level
1-Methoxy-4-(methoxymethyl)benzene, 4-CH3O-C6H4-CH2-OCH3, is heated with excess concentrated HI. Assume that every C(sp^3)-O bond ends up as a C-I bond (the ben... JEE Main level
Optically pure (R)-octan-2-ol is converted by TsCl/pyridine into its tosylate (no bond to the stereocentre is broken). The tosylate is then heated with LiBr in ... JEE Advanced level
Sodium (S)-2-bromopropanoate, CH3CH(Br)COO- Na+, is hydrolysed in dilute aqueous alkali. Assume that the rate-determining step is intramolecular displacement of... JEE Advanced level
(S)-2-Methyloxirane is treated with sodium methoxide in methanol and then neutralised. Select the correct statements. (Priorities at the stereocentre of the epo... JEE Advanced level
The reaction RBr + Nu- -> RNu + Br- was studied at constant temperature. Initial rates were: Run 1, [RBr] = 0.10 M, [Nu-] = 0.10 M, rate = 4.8 x 10^-5 M s^-1; R... JEE Advanced level
(2R,5R)-5-Chlorohexan-2-ol is treated with a dilute aqueous solution of NaOH and the only reaction is intramolecular SN2 (the alkoxide displaces chloride at C5;... JEE Advanced level
In which of the following clean SN2 reactions of an enantiopure substrate does the product carry the same CIP letter (R or S) as the substrate, even though the ... JEE Advanced level
cis-4-tert-Butylcyclohexyl tosylate and trans-4-tert-butylcyclohexyl tosylate are each treated with NaN3 in DMF, and substitution occurs by SN2 (the tert-butyl ... JEE Advanced level
Optically pure (S)-2-iodooctane is stirred in acetone with a very large excess of radioactive Na^*I, so the labelled iodide concentration stays essentially cons... JEE Advanced level
textitcis-1-Bromo-3-methylcyclohexane, which is (1R,3S)-1-bromo-3-methylcyclohexane (numbering from the carbon bearing bromine), is treated with NaI in acetone ... JEE Advanced level
Select the correct statements about SN2 reactions of cyclic halides. JEE Advanced level