The AuI‐catalyzed reaction of 2‐(1‐alkynyl)‐2‐alken‐1‐ones with azomethine imines regio‐ and diastereoselectively affords furo[3,4‐d]tetrahydropyridazines in a tandem cyclization/intermolecular [3+3]‐cycloaddition process under mild conditions. By employing a chiral gold catalyst (prepared in situ from a Taddol‐derived phosphine‐phosphite ligand, Me2SAuCl, and AgOTf) high yields and enantioselectivities
Asymmetric Hydroformylation Using Taddol-Based Chiral Phosphine−Phosphite Ligands
作者:Tobias Robert、Zohar Abiri、Jeroen Wassenaar、Albertus J. Sandee、Steffen Romanski、Jörg-Martin Neudörfl、Hans-Günther Schmalz、Joost N. H. Reek
DOI:10.1021/om9009735
日期:2010.1.25
High-pressure NMR of the active catalyst [HRh(P−P)(CO)2] (P−P = 10h) revealed an equatorial-apical coordination of the ligand at rhodium. Temperature dependency of the coupling constants observed during the experiment indicates equilibrium between the two equatorial-apical isomers, with the isomer in which the phosphite occupies the equatorial position being the dominant species.