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[摘要]：Asym., rhodium-catalyzed hydroformylation of terminal and internal aryl alkenes with diazaphospholane ligands is reported. Under partially optimized reaction conditions, high enantioselectivity (>90% ee) and regioselectivities (up to 65:1 a:b) are obtained for most substrates. For terminal alkenes, both enantioselectivity and regioselectivity are proportional to the carbon monoxide partial pressure, but independent of hydrogen pressure. Hydroformylation of p-substituted styrene derivs. gives the highest regioselectivity for substrates bearing electron-withdrawing substituents. A Hammett anal. produces a pos. linear correlation for regioselectivity. |
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