Asymmetric synthesis of tetrahydrolipstatin and valilactone
Case-Green SC., Davies SG., Roberts PM., Russell AJ., Thomson JE.
The highly diastereoselective aldol reaction between acyl complexes of the iron chiral auxiliary [(η 5 -C 5 H 5 )Fe(CO)(PPh 3 )] and β-hydroxy aldehydes (obtained via a Noyori asymmetric hydrogenation), followed by a tandem oxidative decomplexation-cyclisation process gives access to β-substituted and α,β-disubstituted β-lactones in high ee. This methodology has been employed in the asymmetric syntheses of tetrahydrolipstatin and valilactone. © 2008 Elsevier Ltd. All rights reserved.