K. Yamanari et al., CH PI INTERACTION IN LINKAGE ISOMERS OF BIS(2,2'-BIPYRIDINE)RUTHENIUM(II) COMPLEXES WITH PYRIMIDINE-2-THIONE AND RELATED LIGANDS/, Chemistry Letters, (1), 1996, pp. 35-36
Ruthenium(II) complexes containing nine pyrimidine-2-thione [Ru(L-N,S)
(bpy)(2)](+) (HL = pyrimidine-2-thione; bpy = 2,2'-bipyridine) are pre
pared and characterized. Two linkage isomers exist for most of the com
plexes with unsymmetrical ligands. The isomeric ratios are interpreted
by CH/pi attractive interaction between the 4- or 6-alkyl group of th
e thione ligands and the pi-system of bpy.