Au(I)/Au(III)-Catalyzed Annulative Addition of Alkynes to Aryl Iodides
Hongyan Liu1, Bo Xu1
1Key Laboratory of Science and Technology of Eco-Textiles, Ministry of Education, College of Chemistry and Chemical Engineering, Donghua University, Shanghai 201620, China.
Abstract:
We present a ligand-enabled, gold-catalyzed syn-1,2-carbohetero-functionalization of both internal and terminal alkynes with o-iodo-arylamides. The transformation integrates a tandem oxidative addition and syn-auration, affording a diverse array of syn-carbohetero-functionalization products in yields of up to 95%. Distinct from the anti-addition typically observed in intermolecular gold catalysis, the involvement of intramolecular annulative cyclization dictates a selective syn-addition pathway. Leveraging Au(I)/Au(III) redox catalysis, this strategy establishes a distinct cyclization strategy that exhibits excellent functional-group tolerance and enables late-stage modification of complex pharmaceutical scaffolds.
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