Novel heterometallic isopropoxides of the lanthanides(III) and yttrium(III) with the formula [LnCl(3-x) {Sn-2(OPri)(9)}(x)] (Ln = La, Pr, Nd, Lu and Y; x = 2 or 3) have been synthesized by the reactions of LnCl(3) . 3Pr(i)OH with KSn2(OPri)(9) in 1:2 and 1:3 molar ratio in benzene. These complexes have been characterized by elemental analyses, isopropoxy group estimations and molecular weight measurements. Their spectral [IR, electronic, multinuclear (H-1,C-13, Sn-119) NMR] properties have been studied and discussed.