Intermolecular Hydroalkoxylation and Hydrocarboxylation of 2-Azadienes with High Efficiency
Juan M I Serviano1, Erik J T Phipps1, Patrick L Holland1
1Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States.
Abstract:
Described here is a method for intermolecular hydroalkoxylation and hydrocarboxylation of 2-azadienes through cobalt-catalyzed hydrogen atom transfer and oxidation. This protocol provides a source of 2-azaallyl cation equivalents under mild conditions, is chemoselective in the presence of other C═C double bonds, and requires no excess amount of added alcohol or oxidant. Mechanistic studies suggest that the selectivity arises from lowering the transition state that leads to the highly stabilized 2-azaallyl radical.
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