Asymmetric synthesis of (S)-(−)-N-acetylcolchinol via Ullmann biaryl coupling
作者:Simon D. Broady、Michael D. Golden、John Leonard、James C. Muir、Mickael Maudet
DOI:10.1016/j.tetlet.2007.04.103
日期:2007.6
A modified Ziegler Ullmann coupling process has been developed as the key step in an effective synthesis of (S)-(−)-N-acetylcolchinol, analogues of which are selective vascular targeting agents with potential importance in cancer chemotherapy. Asymmetric induction is achieved by enamide hydrogenation using FerroTANE catalysts.
Short electrochemical asymmetric synthesis of (+)-<i>N</i>-acetylcolchinol
作者:Yi Du、Adelaide Lunga、Aleksandr E. Rubtsov、Andrei V. Malkov
DOI:10.1039/d2gc02321k
日期:——
A shortsynthesis of N-acetylcolchinol using a greener and step-economical pathway is reported where all the redox reactions, except for the asymmetric reduction, were carried out electrochemically, replacing protocols that employ transition metals or stoichiometric hazardous reagents. In a 4-step racemic sequence, chemoselective reduction of chalcone and intramolecular oxidative arene–arene coupling
Asymmetric enamide hydrogenation in the synthesis of N-acetylcolchinol: a key intermediate for ZD6126
作者:Ian C. Lennon、James A. Ramsden、Catherine J. Brear、Simon D. Broady、James C. Muir
DOI:10.1016/j.tetlet.2007.04.090
日期:2007.6
A synthesis of N-acetylcolchinol, a keyintermediate in the synthesis of ZD6126, was developed. The enantiodifferentiating step required the catalytic asymmetric hydrogenation of an enamide. After screening a range of metal and ligand combinations it was found that (S,S)-iPr–FerroTANE Ru(methallyl)2 and [(S,S)-tBuFerroTANE Rh(COD)]BF4 gave both high enantioselectivity (>90% ee) and high catalyst utility