ZnBr2 was found to catalyze formation of propargyl and propargylic Grignard reagents, and thus put an end to the standard method using a mercury catalyst. The Grignard reagents were submitted to addition reaction with carbonyl compounds and allylation with the cyclic monoacetate to afford the propargyl-type products selectively. Furthermore, the product from the monoacetate was transformed to an acetylene analogue of 2-(5, 6-epoxyisoprostane ...
