S. Miki, K. Nakamoto, J. Kawakami
Feb 1, 2008
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Influential Citations
8
Citations
Journal
Synthesis
Abstract
The highly reproducible preparation of ethyl bromozinc-acetate was achieved by a convenient procedure in which an excess amount of zinc powder was subjected to activation by chlorotri-methylsilane, followed by dropwise addition of ethyl bromoacetate. From the resultant solution of this Reformatsky reagent, crystalline ethyl bromozincacetate was isolated and its crystal structure was elucidated as its tetrahydrofuran-coordinated dimer (BrZnCH 2 CO 2 Et·THF) 2 by X-ray crystal structure analysis. Although it had a dimeric structure similar to the TERT-butyl bromo-zinc-acetate crystal, the two had different stereochemistry in the zinc-containing eight-membered ring (ZnCH 2 CO) 2 . The crystalline reagent obtained possessed satisfactory reactivity and stability for practical use. On the other hand, by preparing the tetrahydrofuran-free ethyl bromozincacetate in such solvents as 1,2-dimethoxyethane or cyclopentyl methyl ether, unintended crystallization could be successfully prevented.