Propargyl bromide as an excellent alpha-bromoacetone equivalent: convenient and new route to alpha-aroylacetones.
[reaction: see text] A variety of alpha-aroylacetones 4a-g have been prepared in excellent yields following a new protocol wherein alpha-aminonitriles 1a-g as the aryl acyl anion equivalents readily react with propargyl bromide as the alpha-bromoacetone equivalent. The alkylated product undergoes one-pot unmasking of the keto functionality along with Markovnikov's hydration of the terminal alkyne with CuSO4 x 5H2O in aqueous methanol at 60 degrees C to furnish the desired target in excellent isolated yields.
Mahalingam
Sakkarapalayam M
SM
Department of Chemistry, Indian Institute of Technology Madras, Chennai 600 036, India.
Aidhen
Indrapal Singh
IS