Synthesis of Hexahydropyridazines by [4 + 2] Cycloaddition of Donor-Acceptor Cyclobutanes and

Authors

Jackie Wu
Paul Winiarz
Dhwanish Patel
Johanna de Jong
David Tong
Tristan Chidley
Naresh Vemula
Brian L Pagenkopf

Document Type

Article

Publication Date

4-17-2020

Journal

Organic letters

Volume

22

Issue

8

First Page

3140

Last Page

3144

URL with Digital Object Identifier

https://doi.org/10.1021/acs.orglett.0c00896

Abstract

The GaCl₃-catalyzed [4+2] cycloaddition between alkoxy- and aryl-activated donor-acceptor cyclobutane diesters and cis-diazene 1a (4-phenyl-1,2,4-triazoline-3,5-dione, PTAD) is disclosed. The reaction provides hexahydropyridazine derivatives as single diastereomers in good to excellent yields in most cases. Structural assignment of the cycloadduct 3b was unambiguously established by single crystal X-ray diffraction.