On the Synthesis of Nitrilium Salts from Nitriles and Chloroformates

All articles of this category Nitriles react with methyl or ethyl chloroformate ( 2a,b ) and antimony(V) chloride to give high yields of N -methyl-, or N -ethylnitrilium hexachloroantimonates 3,4 . With butyl chloroformate ( 2c ) N -(1-methylpropyl)nitrilium salts 6 are obtained. These products arise from a 2-butyl cation, which is formed prior to alkylation of the nitrile. Isobutyl chloroformate ( 2d ), (2- tert -butylcyclohexyl) chloroformate ( 2e ), menthyl chloroformate ( 2f ), 2,2-dimethylpropyl chloroformate ( 2g ), and 3-methylbutyl chloroformate ( 2h ) react with nitriles to give N - tert -alkylnitrilium salts, 11,13,15,19 , which were characterized by hydrolysis to amides. With phenyl chloroformate ( 2i ) benzonitriles react in a 1 :2 ratio to furnish 2-phenoxy-1,3,5-oxadiazinium salts 21 .