Synlett 2010(13): 2033-2036  
DOI: 10.1055/s-0030-1258485
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© Georg Thieme Verlag Stuttgart ˙ New York

Copper(II) and Bismuth(III) Hydroxide Catalyzed Addition Reactions of Hydrazonoester with Allenylboronate in Aqueous Media

Shu Kobayashi*, Taku Kitanosono, Masaharu Ueno
Department of Chemistry, School of Science and Graduate School of Pharmaceutical Sciences,, The University of Tokyo, The HFRE Division, ERATO, Japan Science Technology Agency (JST), Hongo, Bunkyo-ku, Tokyo 110-0033, Japan
Fax: +81(3)56840634; e-Mail: shu_kobayashi@chem.s.u-tokyo.ac.jp;
Further Information

Publication History

Received 6 June 2010
Publication Date:
09 July 2010 (online)

Abstract

Metal-hydroxide-catalyzed addition reactions of hydrazonoester with allenylboronate in aqueous media are described. The propargyl adduct was obtained selectively by using copper(II) hydroxide, whereas the allenyl adduct was produced preferentially using bismuth(III) hydroxide in water-DMF (1:3). The reactions proceeded smoothly in pure water without the use of any organic solvents by addition of a small amount (1.7 mol%) of sucrose.

15

It was confirmed that isomerization of 5 did not occur.