Asymmetric Construction of Six-Membered Rings by Cyclization of Allenes with Dinuclear Gold Catalysis
Youai Qiu1, Jing Zhou1, Junzhao Li1
1Laboratory of Molecular Recognition and Synthesis, Department of Chemistry, Zhejiang University, Hangzhou 310027, Zhejiang (P. R. China).
Abstract:
A simple and efficient method for the synthesis of 1,4-dihydroarenes by gold-catalyzed 6-endo cyclization of benzylic allenes has been developed. Furthermore, asymmetric hydroarylation of enantioenriched allenes has been realized to offer a practical and convergent approach to aromatic ring-fused six-membered cycles containing a chiral stereocenter such as 1,4-dihydronaphthalenes, 1,4-dihydrodibenzo[b,d]thiophenes, and 4,7-dihydrobenzo[b]thiophenes by applying dinuclear [(dppm)Au2 Cl2 ] [dppm=methylenebis(diphenylphosphane)] combined with AgOTf as the catalyst to ensure the high efficiency of chirality transfer. ESI-MS has been applied to characterize some of the key reactive dinuclear gold intermediates successfully.
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