The first solid-phase synthesis of bis(oxazolinyl)pyridine ligands.
Chiral Pybox (pyridine-2,6-bis(oxazoline)) ligands can be cleanly and efficiently prepared on polystyrene support via a five-step solid-phase synthetic sequence. Cu(I)-complexed polymer-bound Pybox was used as a catalyst in the first heterogeneously catalyzed asymmetric addition of alkynes to imines. Best enantioselectivity was observed with (t)Bu-substituted oxazolines.
Weissberg
Avi
A
School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel-Aviv University, Tel-Aviv 69978, Israel.
Halak
Baruch
B
Portnoy
Moshe
M