Synthesis and characterisation of chiral Cu(I) complexes with substituted-pyrrolidine-ligands bearing a triethoxysilyl group and preparation of heterogenised catalysts on USY-zeolites

A series of new copper complexes of formula [Cu(L-L) (CH3CN)]X (X = ClO4, PF6 where L-L = (S)-2-R-pyrrolidine (1), (S)-1-R-2-t-butylaminocarbonylpyrrolidine (2), (S)-1-R-2-(1-naphthylaminocarbonyl)pyrrolidine (3), (S)-1-R-2-(1-naphthylaminomethyl)pyrrolidine (4), (2S,4S)-4-amino-1-R-2-t-butylaminocarbonylpyrrolidine (5) (R = (3-triethoxysilylpropyl)aminocarbonyl) have been prepared, characterised and supported on a modified ultrastable Y-zeolite containing supermicropores by a covalent bond. The complexes anchored on the zeolite are easily recycled and show a similar catalytic activity to the free complexes in homogeneous medium for cyclopropanations of olefins.