ORGANOBISMUTH(V) COMPLEXES CONTAINING BIFUNCTIONAL LIGANDS - HYDROGEN-BONDED EXTENDED STRUCTURES AND STEREOSELECTIVITY

New bismuth(v) complexes with the general formula of (BiR3)-R-v(O2CR') (2) have been synthesized by the reaction of BiR3Cl2 with Ag(O2CR'), w here R is an aromatic ligand and R' a substituent containing a hydroxy l group. The role of these new bismuth(v) complexes as building blocks to form hydrogen-bonded extended structures in the solid has been exa mined by single-crystal X-ray diffraction analyses. The bismuth atoms in these compounds adopt distorted trigonal-bipyramidal geometries. Th e hydrogen-bonding pattern and the extended structure displayed have b een found to be highly dependent on the R and the R' groups. Unusual h ydrogen-bonded extended structures such as double strands and double l ayers have been observed. In an attempt to obtain chiral helical exten ded structures, the reactions of BiR3Cl2 with several silver salts, Ag (O2CR), where R* contains one chiral centre and a hydroxyl group, wer e examined. The bismuth(v) centre shows an unusual stereoselectivity t owards the chiral ligand RCO2-. When a racemic mixture of Ag(O2CR*) w as used only the enantiomers (R,R)- and (S,S)-BiR3(O,CR)(2) were obta ined.