Question

1. Name two more parameters that can be easily explored by high-throughput experimentation for Suzuki coupling reactions and how those parameters affect the reaction.

Answer 1

following parameters are effected on suzuki coupling reaction

1. nature of aryl halide

2. nature of aryl/alkyl boronic acid/ester

3. nature  of base

1. nature of aryl halide:

(i) we can can explain nature of Ar-X by using Ar-I, Ar-Br, Ar-Cl, Ar-F. here the bond length between Ar-I is more than other Ar-X (X = Br,Cl, F). so bond strength very weak in Ar-I. due this Ar-I readly participate in suzuki coupling reaction than other Ar-X. therfore the reactivity order of Ar-X follows Ar-I > Ar-Br > Ar-Cl > Ar-F.

(ii) if Ar-X has substituents, it will effect on rate of reaction. usually electron donating substiuent on Ar-X are readly participate in suzuki coupling reaction. therefore reactivity order of substiuted aryl halide are follows electron donating substituted Ar-X > Ar-X > electron withdrwaing substituted Ar-X.

2. nature of aryl/alkyl boronic acid/ester

(i) usually boronic ester are readly particpated in suzuki coupling reaction than boronic acid.

(ii) size of Aryl/alkyl group whic has attached to boronic ester/acid also efffected on rate suzuki coupling reaction. smaller alkyl/aryl group is readly participate in suzuki coupling reaction than bulkier alkyl/aryl group.

3. nature  of base

milder base is favorouble for suzuki coupling reaction.