Keck, G. E.; Poudel, Y. B.; Welch, D. S.; Kraft, M. B.; Truong, A. P.; Stephens, J. C.; Kedei, N; Lewin, N. E.; Blumberg, P. M. Organic Letters 2009, 11, 593-596.

Keck. G. E.; Kraft, M. B.; Truong, A. P.; Li, Wei; Sanchez, C. C.; Kedei, N.; Lewin, N. E.; Blumberg, P. M. American Chemical Society 2008, 130, 6660-6661.

Mineeva, I.V.; Kulinkovich, O. G. Russian Journal of Organic Chenistry 2008, 44, 1261-1266.

The Mineeva lab group experimented with the synthesis of methyl 3-bromomethylbut-3-enoate to acid esters.  The formation of these acid esters were carried through the most smoothly when aqueous ammonium chloride in tetrahydrofuran and zinc were present in the reaction mixture.  Methyl 3-bromomethylbut-3-enoate undergoes a condensation reaction with electrophiles to form acid esters.  To form the intermediates—δ-hydroxy-β-methylidenealkanoic acid esters—an aldehyde and an allyl bromide were reacted together.  Here, it is essential to note that the reaction occurred successfully in when the presence of both zinc and aqueous ammonium chloride in tetrahydrofuran.  Without aqueous ammonium chloride in tetrahydrofuran, the scientists obtained a product that arose through a lactonization reaction and a migration of a carbon double bond.  During this reaction, an ester is formed with a C=O group.  This reaction is similar to the ester formation that is seen in the formation of (E)-(4S, 6R, 7R)-7-((benzyloxy)methoxy)-6-((4-methoxybenzyl)oxy)oct-1-en-4-yl 5-((tert-butyldimethlysilyl)oxy)-2,2-dimethylpent-3-enoate.