【摘 要】
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A series of DFT determinations have been employed to quantitatively characterize the mechanism and origins of regioselectivity,substituent effect and coupli
【机 构】
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College of Chemistry,Beijing Normal University,Beijing 100875,China
论文部分内容阅读
A series of DFT determinations have been employed to quantitatively characterize the mechanism and origins of regioselectivity,substituent effect and coupling partner selectivity of titled reactions.All DFT calculations in this work were performed with the B3LYP method,employing the standard double-ζ valence polarized(DZVP)all-electron basis set for all atoms.Solvent effect of acetonitrile(Σ= 35.688)were evaluated by polarizable continuum model(PCM),plus our IDSCRF radii.The obtained results indicate that the catalytic cycle involves C-H activation,migratory insertion,reductive elimination,oxidative addition,and separation of product & catalyst recovery,in which the alkyne migratory insertion step is rate-determining one.The significant selectivity(entry 8)of coupling partner MIDA boronates is due to the association between CsOPiv and sp2 B atom in alkyne.The role of Cu(OAc)2 that facilitate the reaction(entry 6)is assist internal oxidant group to change the valence state of Rh center from Rh(I)to Rh(Ⅲ).
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