The authors would like to dedicate this article to Professor Dieter Enders on the
occasion of his 70th birthday.
Abstract
Amphiphilic polystyrene-poly(ethylene glycol) resin-supported chiral imidazoindole
phosphines (PS-PEG-L*), (3R,9aS)-2-aryl-3-(2-dialkylphosphino)phenyltetrahydro-1H-imidazo[1,5-a]indol-1-one, bearing PPh2, P(t-Bu)2, and P(c-Hex)2 groups were designed and prepared with a view toward using them in aqueous heterogeneous
asymmetric Suzuki–Miyaura biaryl coupling. The asymmetric coupling of 2-substituted
1-iodonaphthalenes and 2-substituted naphthalen-1-ylboronic acid took place in water
under heterogeneous conditions in the presence of 10 mol% palladium of PS-PEG-L*-Pd
complexes to give up to 94% ee of (S)-2,2′-disubstituted 1,1′-binaphthyls.
Key words
asymmetric catalysis - biaryls - cross-coupling - palladium - Suzuki–Miyaura coupling
- catalysis in water - heterogeneous catalysis