Studies on quinazolines.: 11.: Intramolecular imidate-amide rearrangement of 2-substituted 4-(ω-chloroalkoxy)quinazoline derivatives.: 1,3-O → N shift of chloroalkyl groups via cyclic 1,3-azaoxonium intermediates

被引：30

作者：

Chen, GS ^{[1
]}

Kalchar, S ^{[1
]}

Kuo, CW ^{[1
]}

Chang, CS ^{[1
]}

Usifoh, CO ^{[1
]}

Chern, JW ^{[1
]}

机构：

[1] Natl Taiwan Univ, Coll Med, Sch Pharm, Taipei 10018, Taiwan

来源：

JOURNAL OF ORGANIC CHEMISTRY | 2003年 / 68卷 / 06期

关键词：

D O I：

10.1021/jo0263420

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The co-chloroalkylation of 2-substituted quinazolin-4(3H)-one derivatives 1 and 2 with Br-(CH2)(n)-Cl (n = 2-4) and the intramolecular imidate-amide rearrangement of the alkylated products are described. At room temperature, the 2-phenyl substituent promoted O-alkylation, whereas the less steric 2-benzyl group led to a higher ratio of N-alkylation. The investigation of the O-alkylated products, 4-omega-chloroalkoxyquinazolines, revealed that the migration of omega-chloroethyl and omega-chloropropyl groups from oxygen to nitrogen should be intramolecular via five- and six-membered cyclic 1,3-azaoxonium intermediates, respectively. Competition between rearrangement and nucleophilic substitution results in the formation of 7a,b and 8a,b from the nucleophilic substitution of 4a,b and 6a,b, respectively.

引用

页码：2502 / 2505

页数：4