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Synthesis of Hexahydropyridazines by [4 + 2] Cycloaddition of Donor-Acceptor Cyclobutanes and -Diazenes. | LitMetric
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Synthesis of Hexahydropyridazines by [4 + 2] Cycloaddition of Donor-Acceptor Cyclobutanes and -Diazenes.

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

Org Lett

Department of Chemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7, Canada.

Published: April 2020

The GaCl-catalyzed [4 + 2] cycloaddition between alkoxy- and aryl-activated donor-acceptor cyclobutane diesters and -diazene (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. The structural assignment of the cycloadduct was unambiguously established by single-crystal X-ray diffraction.

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 Source
http://dx.doi.org/10.1021/acs.orglett.0c00896DOI Listing

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