Synlett 2004(3): 534-536  
DOI: 10.1055/s-2004-815433
LETTER
© Georg Thieme Verlag Stuttgart · New York

InCl3-Promoted Allylation of Aldehydes in Ionic Liquid: Scope and Enantioselectivity Studies

Jun Lua, Shun-Jun Ji*a, Rong Qiana, Jian-Ping Chena, Yu Liua, Teck-Peng Loh*a,b
a College of Chemistry and Chemical Engineering of Suzhou University, Suzhou215006, P. R. China
e-Mail: shunjun@suda.edu.cn;
b Department of Chemistry, 3 Science Drive 3, National University of Singapore, 117543 Singapore
Fax: +65(677)91691; Fax: +86(512)65224873; e-Mail: chmlohtp@nus.edu.sg;
Further Information

Publication History

Received 10 December 2003
Publication Date:
26 January 2004 (online)

Abstract

Indium trichloride was successfully applied to allylation reaction of aldehydes using allytributyltin in ionic liquids. This accelerated catalytic system afforded the allylated products of various aldehydes in moderate to high yields. Preliminary studies on the enantioselectivity of this type of reaction have resulted in low to moderate enantioselectivities.

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Typical Experimental Procedure: To a 25 mL round-bottom flask containing an egg-shaped stirring bar were added [hmin+][Cl-] (0.5mL) and InCl3 (53 mg, 0.24 mmol). After stirring at 25 °C for 15 min, benzaldehyde (21.2mg, 0.2mmol) was added followed by allytributyltin (81.9 mg, 0.24 mmol). The reaction mixture was stirred at 25 °C for 16 h. Then the mixture was extracted with EtOAc (3 × 10 mL). The combined organic extracts were washed with brine, dried over anhyd Na2SO4, concentrated under vacuum, and purified by silica gel column chromatography to afford 80% of the product as a colorless oil.