A theoretical study on the alkene insertion step in Rh-Yanphos catalyzed hydroformylation

This paper studied the mechanism of the alkene insertion elementary step in the asymmetric hydroformylation (AHF) catalyzed by RhH(CO)2[(R,S)-Yanphos] using four alkene substrates (CH2CHPh, CH2CHPh(p)Me, CH2CHC(O)OCH3 and CH2CHOC(O)Ph, abbreviated as A1–A4). Interestingly, the equatorial vertical coordination mode (A mode) with respect to the Rh center was found for A1 and A2 but not for A3 and A4, although the equatorial in-plane coordination mode (E mode) was found for A1–A4. The relative energy of the E mode of the η2-intermediates is lower than that of the A mode. In the alkene insertion step, Path 1 is more favorable than Path 2 for this system. As for A1 and A2, there could be a transformation between 2eq and 2ax.

This paper studied the mechanism of the alkene insertion elementary step in the asymmetric hydroformylation (AHF) catalyzed by RhH(CO)2[(R,S)-Yanphos] using four alkene substrates (CH2CHPh, CH2CHPh(p)Me, CH2CHC(O)OCH3 and CH2CHOC(O)Ph, abbreviated as A1–A4). Interestingly, the equatorial vertical coordination mode (A mode) with respect to the Rh center was found for A1 and A2 but not for A3 and A4, although the equatorial in-plane coordination mode (E mode) was found for A1–A4. The relative energy of the E mode of the η2-intermediates is lower than that of the A mode. In the alkene insertion step, Path 1 is more favorable than Path 2 for this system. As for A1 and A2, there could be a transformation between 2eq and 2ax.Figure optionsDownload as PowerPoint slide