α-Selective syn-Carbotrifluoromethylthiolation of Alkynes
Prachi Shah1, Wojciech Chaładaj1
1Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
Abstract:
Trifluoromethylthiolative difunctionalization of alkynes typically proceeds in an anti-fashion delivering the SCF3 group in the β-position (anti-Markovnikov). Herein, we disclose a vicinal syn-arylation-trifluoromethylthiolation of alkynes enabling α-selective introduction of the SCF3 group (Markovnikov). The unique selectivity was achieved via a merge of Ni-catalyzed carbomagnesiation with a subsequent Cu-mediated trifluoromethylthiolation of the resulting vinyl-magnesium species. The former component of the sequential process determines both the regio- and stereoselectivity of the overall transformation.
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