Asymmetric hydrogenation of di and trisubstituted enol phosphinates with N,P-ligated iridium complexes.
The iridium-catalyzed asymmetric hydrogenation of various di- and trisubstituted enol phosphinates has been studied. Excellent enantioselectivities (up to >99% ee) and full conversion were observed for a range of substrates with both aromatic and aliphatic side chains. Enol phosphinates are structural analogues of enol acetates, and the hydrogenated alkyl phosphinate products can easily be transformed into the corresponding alcohols with conservation of stereochemistry. We have also hydrogenated, in excellent ee, several purely alkyl-substituted enol phosphinates, producing chiral alcohols that are difficult to obtain highly enantioselectively from ketone hydrogenations.
Cheruku
Pradeep
P
Department of Biochemistry and Organic Chemistry, Uppsala University, Box 576, 751 24 Uppsala, Sweden.
Diesen
Jarle
J
Andersson
Pher G
PG
D002384:Catalysis; D006865:Hydrogenation; D007495:Iridium / Q000737:chemistry*; D007659:Ketones / Q000737:chemistry; D008024:Ligands; D008956:Models, Chemical; D009584:Nitrogen / Q000737:chemistry*; D009943:Organophosphorus Compounds / Q000737:chemistry*; D010721:Phosphinic Acids / Q000737:chemistry*; D010758:Phosphorus / Q000737:chemistry*; D013237:Stereoisomerism
D007659:Ketones; D008024:Ligands; D009943:Organophosphorus Compounds; D010721:Phosphinic Acids; D010758:Phosphorus; D007495:Iridium; D009584:Nitrogen