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Published on: May 26, 2019
Highly Selective Manganese(I)/Lewis Acid Cocatalyzed Direct C-H Propargylation Using Bromoallenes
Can Zhu1, Jonas Luca Schwarz1, Sara Cembellín1
1Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut, Corrensstrasse 40, 48149, Münster, Germany.
Abstract:
A manganese(I)/Lewis acid cocatalyzed direct C-H propargylation with high selectivity has been developed. BPh3 was discovered to not only promote the reactivity, but also enhance the selectivity. Secondary, tertiary, and even quaternary carbon centers at the propargylic position could be directly constructed. Both internal and terminal alkynes are easily accessible. The chirality was successfully transferred from an axially chiral allene to central chirality. The reactivity of the manganese catalyst in this reaction was found to be unique among transition metal catalysts.
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