Enantioselective carbonyl propargylation by iridium-catalyzed transfer hydrogenative coupling of alcohols and propargyl chlorides.
It takes alkynes! Exposure of propargyl chlorides to primary benzylic alcohols in the presence of [Ir(cod){(R)-segphos}]OTf (cod = 1,5-cyclooctadiene, segphos = 5,5'-bis(diphenylphosphino)-4,4'-bi-1,3-benzodioxole, Tf = trifluoromethanesulfonyl) results in hydrogen exchange to give allenyliridium-aldehyde pairs that combine to form products of propargylation with high ee value (see scheme). The reaction can also be conducted using aldehydes.
University of Texas at Austin, Department of Chemistry and Biochemistry, 1 University Station-A5300, Austin, TX 78712-1167, USA.
Sang Kook
SK
Woo
Laina M
LM
Geary
Michael J
MJ
Krische
D000438:Alcohols / Q000138:chemical synthesis* / Q000737:chemistry*; D000447:Aldehydes / Q000737:chemistry; D000480:Alkynes / Q000737:chemistry*; D002384:Catalysis; D006865:Hydrogenation; D007495:Iridium / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D010084:Oxidation-Reduction; D013237:Stereoisomerism
D000438:Alcohols; D000447:Aldehydes; D000480:Alkynes; D009942:Organometallic Compounds; D007495:Iridium