Hydrogen-mediated aldol reductive coupling of vinyl ketones catalyzed by rhodium:: High Syn-selectivity through the effect of tri-2-furylphosphine

[GRAPHICS] Catalytic hydrogenation of methyl vinyl ketone (MVK) and ethyl vinyl ketone (EVK) in the presence of diverse aldehydes at ambient temperature and pressure using tri-2-furylphosphine-ligated rhodium catalysts enables formation of aldol products with high levels of syn-diastereoselectivity. A progressive increase in diastereoselectivity is observed upon sequential replacement of phenyl residues for 2-furyl residues (Ph3P, FurPh(2)P, Fur(2)PhP, Fur(3)P). Hydrogen-labile functional groups, including alkynes, alkenes, benzylic ethers, and nitroarenes, remain intact under the coupling conditions.