Construction of Hexahydrophenanthrenes By Rhodium(I)‐Catalyzed Cycloisomerization of Benzylallene‐Substituted Internal Alkynes through C−H Activation |
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| Authors: | Yasuaki Kawaguchi Dr Shigeo Yasuda Prof?Dr Chisato Mukai |
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| Institution: | Division of Pharmaceutical Sciences, Graduate School of Medical Sciences, Kanazawa University, Kakuma-machi, Kanazawa, Japan |
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| Abstract: | The treatment of benzylallene‐substituted internal alkynes with RhCl(CO)2]2 effects a novel cycloisomerization by C(sp2)?H bond activation to produce hexahydrophenanthrene derivatives. The reaction likely proceeds through consecutive formation of a rhodabicyclo4.3.0] intermediate, σ‐bond metathesis between the C(sp2)?H bond on the benzene ring and the C(sp2)?RhIII bond, and isomerization between three σ‐, π‐, and σ‐allylrhodium(III) species, which was proposed based on experiments with deuterated substrates. |
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| Keywords: | alkynes allenes C− H activation cycloisomerization rhodium |
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