Synthesis 2017; 49(04): 745-754
DOI: 10.1055/s-0036-1588333
paper
© Georg Thieme Verlag Stuttgart · New York

A Facile Synthesis of 4-Tetrazolyl-Substituted 4H-3,1-Benzoxazines through Sequential Passerini-Azide/Acylation/Catalytic Aza-Wittig Reaction

Zhi-Lin Ren
Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Central China Normal University, Wuhan 430079, P. R. of China   Email: mwding@mail.ccnu.edu.cn
,
Jian-Chao Liu
Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Central China Normal University, Wuhan 430079, P. R. of China   Email: mwding@mail.ccnu.edu.cn
,
Ming-Wu Ding*
Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Central China Normal University, Wuhan 430079, P. R. of China   Email: mwding@mail.ccnu.edu.cn
› Author Affiliations
Further Information

Publication History

Received: 25 July 2016

Accepted after revision: 22 September 2016

Publication Date:
14 October 2016 (online)


Abstract

A facile synthesis of 4-tetrazolyl-4H-3,1-benzoxazines by a Passerini-azide/acylation/catalytic aza-Wittig sequence was developed. The Passerini-azide reactions of 2-azidobenzaldehydes, trimethylsilyl azide and isocyanides produced tetrazoles, which were further acylated to give the azides in 28–74% overall yields. The catalytic aza-Wittig reactions of the azides generated 4-tetrazolyl-4H-3,1-benzoxazines in good yields, by using a catalytic amount of 3-methyl-1-phenyl phospholene-1-oxide (10 mol%) and TMDS/Ti(i-PrO)4 reductant system.

Supporting Information