A NEW METHOD OF SYNTHESIZING DEOXYBENZOINS FROM 1,3-DIMETHYL-2-(ALPHA-BENZYLOXYBENZYL)IMIDAZOLIUM AND -DIMETHYL-2-(ALPHA-BENZYLOXYBENZYL)BENZIMIDAZOLIUM IODIDES BASED ON WITTIG-TYPE REARRANGEMENT

Authors
MIYASHITA A MATSUOKA Y SUZUKI Y IWAMOTO K HIGASHINO T
Citation
A. Miyashita et al., A NEW METHOD OF SYNTHESIZING DEOXYBENZOINS FROM 1,3-DIMETHYL-2-(ALPHA-BENZYLOXYBENZYL)IMIDAZOLIUM AND -DIMETHYL-2-(ALPHA-BENZYLOXYBENZYL)BENZIMIDAZOLIUM IODIDES BASED ON WITTIG-TYPE REARRANGEMENT, Chemical and Pharmaceutical Bulletin, 45(8), 1997, pp. 1235-1242
Citations number
26
Categorie Soggetti
Pharmacology & Pharmacy",Chemistry
Journal title
Chemical and Pharmaceutical Bulletin → ACNP
ISSN journal
00092363
Volume
45
Issue
8
Year of publication
1997
Pages
1235 - 1242
Database
ISI
SICI code
0009-2363(1997)45:8<1235:ANMOSD>2.0.ZU;2-D
Abstract
The treatment of -dimethyl-2-(alpha-benzyloxybenzyl)benzimidazolium io dides 1 with a base gave deoxybenzoins 2 in moderate yields. Sodium hy dride (NaH), potassium carbonate (K2CO3), and cesium carbonate (Cs2CO3 ) were effective bases in this reaction. Deoxybenzoins 2 were produced through rearrangement of the benzyl group followed hy expulsion of th e 1,3-dimethylbenzimidazolium ylide (A). The rearrangement proceeds in a way similar to Wittig rearrangement. Deoxybenzoins 2 were also form ed in good yields from 1,3-dimethyl-2-(alpha-benzyloxybenzyl)imidazoli um iodides 4 upon similar treatment. However, the quaternary salts hav ing a thiazolium moiety 5a and a pyridinium moiety 6a failed to produc e deoxybenzoin (2a).