Hazard in preparing methyl 2-butynoate
Chemical & Engineering News (14 Nov 1994) Vol. 72, No. 46, pp. 4.
In the past, we had made only very small quantities of methyl 2-butynoate and occasionally had a distillation "take off." Recently, attempts to manufacture this product on a larger scale have resulted in violent decomposition.
This has not been an isolated incident. It has occurred on more than one occasion, during distillation of material from different synthetic procedures, namely sodium, lithium, and Grignard derivatives of propyne reacted with methyl chloroformate and also from the esterification of 2-butynoic acid. The product has been distilled under vacuum; however, we believe this to be a compound that can decompose violently when exposed to many of the conditions that routinely occur in the workup of organic esters.
We have not exhaustively investigated all of the possible conditions
that led to its decomposition. We have, however, explored enough
different conditions to warn that anyone attempting to manufacture
methyl 2-butynoate should be cautious when attempting to distill
more than a few grams.
page last revised December 7, 1998