Effects of alkyl groups on acidities and basicities in the gas phase. An ab initio molecular orbital study

Abstract

Ab initio molecular orbital theory has been used to investigate the acidities and basicities of alcohols (ROH), alkylamines (RNH₂) and alkynes (RCCH) (R = Me, Et, isopropyl, t-butyl). In all cases, the acidities and basicities increase in the order R = Me < Et < Prⁱ < Bu^t. Analysis of the calculated charge distributions shows that alkyl groups can donate or accept electrons on demand and that the larger alkyl groups examined do this more effectively than the smaller ones.