The Autoxidation of 1‐Phenylalk‐1‐ynes. Proof of oxirenes as intermediates in the oxidation of acetylenes

Abstract

Abstract In the autoxidations of 1‐phenylprop‐1‐yne, 1‐phenylbut‐1‐yne, and 1‐phenyl‐3‐methylbut‐1‐yne a considerable attack at the CC triple bond takes place. Both products of the oxidative cleavage of the CC bond and products formed through the corresponding oxirenes were detected. The oxirenes rearrange via the isomeric ketocarbenes to ketenes, which yield the corresponding carboxylic acids or their esters. A part of the intermediate ketenes is oxidized with decarboxylation to lower ketones. All products were identified and quantitatively determined after LiAlH 4 reduction to the corresponding alcohols.