The first butyltin(IV) homo- and heterobimetallic diethanolaminates

Equimolar reactions of BuSn(OPri)(3) with diethanolamines, RN(CH2CH2OH)(2) (abbreviated as RdeaH(2), where R=H or Me), afford dimeric isopropoxo-bridged six-coordinate butyltin(IV) complexes [{Bu(eta(3)-Rdea)Sn(mu-OPri)}(2)] (R=H (1), Me (2)). Interactions between BuSn(OPri)(3) and diethanolamines (RdeaH2) in a 1: 2 molar ratio yield monomeric derivatives of the type [BuSn(Rdea)(RdeaH)] (R=H (3), R=Me (4)). These homometallic complexes on 1: 1 reactions with an appropriate metal alkoxide form monomeric heterobimetallic complexes of the type [BuSn(Rdea)(2){M(OR')(n)}] (R = H, M = Al, R' = Pr-i, n = 2 (5); R = H, M =Ti, R = Pr-i, n =3 (6); R = H, M = Zr, R' = Pr-i, n =3 (7); R = Me, M = Al, R' = Pr-i, n =2 (8); R =Me, M = Ti, R' =Pr-i, n = 3 (9); R = Me, M = Ge, R' = Et, n = 3 (10)). The driving force behind this work was (i) to explore the utility of homometal complexes (1)-(4) in assembling a metal alkoxide fragment via a condensation reaction and (ii) to gain insights into the structures of new compounds by NMR spectral data. All of these derivatives have been characterized by elemental analysis, spectroscopic (IR, NMR; H-1, Al-27, and Sn-119) studies, and molecular weight measurements. Sn-119 NMR spectral studies indicate that both the homometallic (3) and (4) and heterobimetallic (5)-(9) complexes exist in a solution in an equilibrium of six-and five-coordinated tin(IV) species.