Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals, Vol.342, 241-248, 2000
A hydrogen-bonded organic network with appended chiral metal complexes
Treatment of anthracenebisresorcinol (1.4H) with La((OPr)-Pr-l)(3) and binaphthol (BN.2H) as a chiral ligand affords an amorphous and insoluble 1:2:2 adduct (chiral La host) formulated as (1.2H)(2-).2(LaBN)(+). This formulation suggests that chiral La3+-binaphthoxide moieties are attached to the half-deprotonated hydrogen-bonded network of the host. The chiral La host catalyzes the Michael reaction of dimethyl malonate with cyclohexenone with ee congruent to 70%. The analogous chiral Al host (1.2H)(2-).2(AlBN)(+) obtained from Al(CH3)(3) catalyzes the Diels-Alder reaction between N-crotonoyl-1,3-oxazolidin-2-one and cyclopentadiene with an ee of similar to 75% for the minor exo product.
Keywords:chiral metal catalyst;solid catalyst;hydrogen-bonded network;Michael addition;Diels-Alder reaction;La3+ and Al3+