bulkier the alkyl groups that are attached to the carbonyl, the more strained and less stablewill be the cyanohydrin.(d)Steric effects influence the rate of nucleophilic addition to these two ketones. Carbon is on itsway from tricoordinate to tetracoordinate at the transition state, and alkyl groups are forcedcloser together than they are in the ketone.The transition state is of lower energy when R is smaller. Acetone (for which R is methyl) isreduced faster than 3,3-dimethyl-2-butanone (where R is tert-butyl).(e)In this problem we examine the rate of hydrolysis of acetals to the corresponding ketone oraldehyde. The rate-determining step is carbocation formation.Hybridization at carbon changes from
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