Organic Letters
Letter
pyridine group (1x) was unreactive for the transformation.
Besides, substrates bearing a dibenzylamino group (1za) and 2-
(benzoxycarbonyl)pyrrolidinyl group (1zb) could not be
carbonylated to 2za and 2zb, respectively, mainly due to the
poorer nucleophility of dibenzylamine and benzyl prolinate.
The triazene with a primary amino group like 3-di-p-tolyltriaz-
1-ene (1zc) was recovered under these conditions.
AUTHOR INFORMATION
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Corresponding Author
Notes
The authors declare no competing financial interest.
Finally, a possible reaction pathway was proposed on the
basis of the reported mechanism of palladium-catalyzed
carbonylation reactions involving aryl diazonium salts (Scheme
2).13 First, aryltriazene (1) decomposed to aryldiazonium
ACKNOWLEDGMENTS
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We thank the State of Mecklenburg-Vorpommern, the
Bundesministerium fur Bildung und Forschung (BMBF), and
̈
the Deutsche Forschungsgemeinschaft for financial support. We
also appreciate the general support from Prof. Matthias Beller
of LIKAT.
Scheme 2. Proposed Reaction Mechanism
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ASSOCIATED CONTENT
* Supporting Information
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S
1
Experimental details for the preparation of triazenes and H
and 13C NMR spectra for the substrates and products. This
material is available free of charge via the Internet at http://
C
Org. Lett. XXXX, XXX, XXX−XXX