Synthesis 2022; 54(02): 499-505
DOI: 10.1055/a-1561-5557
paper

Diastereoselective Palladium-Catalyzed [4+1] Cycloadditions of 4-Vinyl-1,4-dihydro-2H-3,1-benzoxazin-2-ones with In Situ Formed Carbenes

Yan-Hua Ma
,
Fan-Xiao Meng
,
Ruo-Nan Wang
,
Ya-Xin Fan
,
Qing-Qiang Su
,
Ji-Yuan Du
We are grateful for financial support from NSFC (21602094), Natural Science Foundation of Shandong Province (ZR2016BB11), and this work was supported by Taishan Scholar Research Fund of Shandong Province.


Abstract

Herein, we present a palladium-catalyzed tandem [4+1] cyclo­addition of 4-vinyl-1,4-dihydro-2H-3,1-benzoxazin-2-ones with ­N-tosyl­hydrazones. The reaction is accomplished by merging the in situ generated aza-ortho-quinone methides (aza-o-QMs) with nucleophilic carbenes. This method enables the construction of diverse indolines with broad functional group compatibility in good yields with high levels of diastereoselectivity under mild conditions.

These authors contributed equally.


Supporting Information



Publication History

Received: 15 June 2021

Accepted after revision: 29 July 2021

Accepted Manuscript online:
29 July 2021

Article published online:
17 September 2021

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