Intramolecular electrophilic aromatic substitution of α-alkylcinnamaldehydes affording 1-alkoxy-2-alkylindenes

被引：10

作者：

Jobashi, Takashi

Kawai, Atsushi

Kawai, Satomi

Maeyama, Katsuya

Oike, Hideaki

Yoshida, Yasuhiko

Yonezawa, Noriyuki ^{[1
]}

机构：

[1] Tokyo Univ Agr & Technol, Dept Organ & Polymer Mat, Tokyo 1848588, Japan

[2] Toyo Univ, Grad Sch Engn, Dept Appl Chem, Kawagoe, Saitama 3508585, Japan

来源：

TETRAHEDRON | 2006年 / 62卷 / 24期

关键词：

1-alkoxy-2-alkylindene; alpha-alkylcinnamaldehyde; alkoxylation; intramolecular electrophilic arylation; acetal;

D O I：

10.1016/j.tet.2006.03.092

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

Treatment of alpha-alkylcinnamaldehydes with orthoesters, alcohols, or thiols in the presence of (BF3OEt2)-O-. induces an intramolecular electrophilic aromatic substitution reaction to afford 1-alkoxy-2-alkylindenes. The reaction mechanisms of the indene formation have been elucidated on the basis of the reaction behaviors of beta-deuterated alpha-methylcinnamaldehyde and the NMR studies of the reaction mixture. The transformation process involves successive reactions, i.e., alkoxylation of the carbonyl carbon of alpha-alkylcinnamaldehydes to form acetals, elimination of alkoxide from the acetals to give alkoxycarbenium ion and gamma-alkoxyallyl cation, and intramolecular electrophilic arylation to afford the indene ring structure. (c) 2006 Elsevier Ltd. All rights reserved.

引用

页码：5717 / 5724

页数：8