Synthesis 2005(2): 279-285  
DOI: 10.1055/s-2004-837291
PAPER
© Georg Thieme Verlag Stuttgart · New York

N-Bromosuccinimide (NBS) Catalyzed Highly Chemoselective Acetalization of Carbonyl Compounds Using Silylated Diols and Pentaerythritol under Neutral Aprotic Conditions

Babak Karimi*, Hassan Hazarkhani, Jafar Maleki
Institute for Advanced Study in Basic Sciences (IASBS), Department of Chemistry, P.O. Box 45195-159, Gava Zang, Zanjan, Iran
Fax: +98(241)4249023; e-Mail: karimi@iasbs.ac.ir;
Further Information

Publication History

Received 9 June 2004
Publication Date:
16 December 2004 (online)

Abstract

Various types of carbonyl compounds are efficiently converted to their 1,3-dioxanes and pentaerythritol diacetals by the use of either 1,3-bistrimethylsiloxy propane (A) or 1,3-bistrimethylsilanyloxy-2,2-bistrimethylsilanyloxymethyl propane (D) and a catalytic amount of N-bromosuccinimide (3-10 mol%) under essentially neutral aprotic condition, respectively. A variety of functionalities such as both aliphatic and phenolic -OTBDMS, -OMe, -OBz, furan ring, double bonds and more significantly phenolic -OTHP survived under the present reaction condition. The efficient conversion of two α-tertiary ketones to their cyclic acetals was also achieved using the present protocol.