Synthesis 2001(5): 0713-0730
DOI: 10.1055/s-2001-12759
PAPER
© Georg Thieme Verlag Stuttgart · New York

Hydrohalogenation Reaction of Substituted 1,2-Allenic Carboxylic Acids, Esters, Amides, Nitriles, and Diphenyl Phosphine Oxides

Shengming Ma*, Hexin Xie, Guangwei Wang, Junliang Zhang, Zhangjie Shi
Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Lu, Shanghai 200032, P. R. China
Fax: +86(21)64166128; e-Mail: masm@pub.sioc.ac.cn;
Further Information

Publication History

Received 27 September 2000
Publication Date:
15 October 2004 (online)

Abstract

The hydrohalogenation reaction of 1,2-allenic carboxylic acids, esters, amides, nitriles, and diphenyl phosphine oxides with HX or MX (X = I, Br, Cl, M = Na, Li) in different solvents, such as HOAc, CF3CO2H, and CF3CO2H-HOAc (1:1) was studied. The reaction is a nucleophilic conjugate addition in nature and provides efficient entries to 3-halo-3-enoic acids, esters, amides, nitriles, and 2-haloallyl diphenyl phosphine oxides. The β,γ- over α,β-selectivity and stereoselectivity depend on the solvent(s) and the temperature applied. In most cases, the Z- and E-isomers can be easily separated by chromatography on silica gel. The subsequent cross-coupling reaction with organometallic reagents and terminal alkynes showed the synthetic potential of these products.