An Agostic Iridium Pincer Complex as a Highly Efficient and Selective Catalyst for Monoisomerization of 1-Alkenes to
Yulei Wang1, Chuan Qin1, Xiangqing Jia1
1State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, 345 Lingling Rd, Shanghai, 200032, China.
Abstract:
A unique Ir complex (tBu NCC P)Ir with the pyridine-phosphine pincer as the sole ligand, featuring a dual agostic interaction between the Ir and two σ C-H bonds from a tBu substituent, has been prepared. This complex exhibits exceptionally high activity and excellent regio- and stereoselectivity for monoisomerization of 1-alkenes to trans-2-alkenes with wide functional-group tolerance. Reactions can be performed in neat reactant on a more than 100 gram scale using 0.005 mol % catalyst loadings with turnover numbers up to 19000.
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