Hydrogen-mediated aldol reductive coupling of vinyl ketones catalyzed by rhodium: high syn-selectivity through the effect of tri-2-furylphosphine.
[reaction: see text]. 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, FurPh2P, Fur2PhP, Fur3P). Hydrogen-labile functional groups, including alkynes, alkenes, benzylic ethers, and nitroarenes, remain intact under the coupling conditions.
Jung
Cheol-Kyu
CK
University of Texas at Austin, Department of Chemistry and Biochemistry, Austin, Texas 78712, USA.
Garner
Susan A
SA
Krische
Michael J
MJ
D000447:Aldehydes / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D006865:Hydrogenation; D007659:Ketones / Q000737:chemistry*; D015394:Molecular Structure; D010720:Phosphines / Q000737:chemistry*; D012238:Rhodium / Q000737:chemistry*; D013237:Stereoisomerism; D014753:Vinyl Compounds / Q000737:chemistry*
D000447:Aldehydes; D007659:Ketones; D010720:Phosphines; D014753:Vinyl Compounds; C514143:tri-2-furylphosphine; D012238:Rhodium