STERIC EFFECTS IN SYSNTHESIS - STERIC LIMITS TO THE ALKYLATION OF NITRILES AND CARBOXYLIC ACIDS

Article abstract of DOI:10.1016/S0040-4020(01)93693-2

The steric limits to the alkylation of aliphatic nitriles and carboxylic acids have been investigated in some detail.For the experimental conditions considered (ionization by i-Pr2NLi in THF followed by alkylation with RI/THF/HMPA) the most hindered nitriles R-CN and carboxylic acids R-CO2H have the same secondary alkyl group R=t-BuiPrCH-, but different tertiary, i.e.R=t-BuiPrEtC- or i-Pr3C- for RCN and R=Et2MeC for RCO2H.A comparison of the relative merits of alkylation of esters, carboxylic acids, and nitriles is considered.