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Title: Construction of Diazo Compounds via Catalytic [3 + 2] Annulation of Vinyldiazoacetates and Their Synthetic Applications
Highly selective formal [3 + 2]-cycloaddition of vinyldiazoacetates with quinone ketals and quinoneimine ketals has been accomplished at room temperature with catalytic amounts of the Brønsted acid triflimide, leading to highly functionalized diazoacetates in good yields. The vinyldiazonium ion generated by electrophilic addition to the vinylogous position of the reactant vinyldiazo compound is the key intermediate in this selective transformation. Both oximidovinyldiazoacetates and those with other vinyl substituents undergo cycloaddition reactions with quinone ketals whose products, after extended reaction times, undergo substrate-dependent 1,2-migration; catalysis by Rh2(OAc)4, HNTf2, and Sc(OTf)3 effects these 1,2-migrations to the same products. However, the products from HNTf2-catalyzed reactions between quinoneimine and oximidovinyldiazoacetates undergo Rh2(OAc)4-catalyzed 1,3-C−H insertion. 1,3-Difunctionalization products are obtained for electrophilic reactions of Eschenmoser’s salt with selected vinyldiazoacetates, but with α-dibenzylaminomethyl ether, 1,6-hydride transfer reactions are observed with oximidovinyldiazoacetates.  more » « less
Award ID(s):
2054845
PAR ID:
10528035
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
ACS Catalysis
Volume:
14
Issue:
9
ISSN:
2155-5435
Page Range / eLocation ID:
6659 to 6666
Subject(s) / Keyword(s):
Brønsted acid catalysis, vinyldiazo compounds, vinyldiazonium ions, cycloaddition, rearrangement
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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