The origin of the ligand-controlled regioselectivity in Rh-catalyzed [(2 + 2) + 2] carbocyclizations: steric vs. stereoelectronic effects

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The origin of the ligand-controlled regioselectivity in Rh-catalyzed [(2 + 2) + 2] carbocyclizations: steric vs. stereoelectronic effects.

Density functional theory calculations demonstrate that the reversal of regiochemical outcome of the addition for substituted methyl propiolates in the rhodium-catalyzed [(2 + 2) + 2] carbocyclization with PPh3 and (S)-xyl-binap as ligands is both electronically and sterically controlled. For example, the ester functionality polarizes the alkyne π* orbital to favor overlap of the methyl-substit...

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The origin of the ligand-controlled regioselectivity in Rh-catalyzed [(2 + 2) + 2] carbocyclizations: steric vs. stereoelectronic effects† †Electronic supplementary information (ESI) available: Computational details, Cartesian coordinates and vibrational frequencies of all optimized structures. See DOI: 10.1039/c5sc02307f Click here for additional data file.

Department of Chemistry, Indiana Universi 47405, USA. E-mail: [email protected] Department of Chemistry, Queen's Universit Canada. E-mail: [email protected] Department of Chemistry, Korea Advanced I Daejeon, 305-701, South Korea Center for Catalytic Hydrocarbon Functiona Daejeon, 305-701, South Korea † Electronic supplementary information Cartesian coordinates and vibrational fr See DOI: ...

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ژورنال

عنوان ژورنال: Chemical Science

سال: 2015

ISSN: 2041-6520,2041-6539

DOI: 10.1039/c5sc02307f