The synthesis and reaction chemistry of new amino-functionalised tin(ii) alkoxides

Sn(ii) derivatives of the aminoalcohols tBu(H)NC(Me)(H)CH 2OH (Htbap, Ib), (R1R2NCH2) 2C(H)OH (R1 = R2 = Me, IIa, Hbdmap; R 1 = tBu, R2 = H, IIb, Hbtbap), (R 1R2NCH2)3COH (R1 = R 2 = Me, IIIa, Htdmap; R1 = tBu, R2 = H, IIIb, Httbap) have been synthesised by reaction of the alcohol with Sn[N(SiMe3)2]2. The structures of the ligands IIb, IIb&middotH2O, IIIb along with Sn(ttbap)2 have been determined; the latter is pseudo-trigonal bipyramidal with nitrogen atoms in axial sites and oxygen atoms and a stereochemically-active lone pair in the equatorial positions. Sn(ttbap)2 reacts with Fe2(CO) 9 in 2:1 ratio (Sn:Fe = 1:1) to afford the donor-acceptor complex (ttbap)2Sn:&rarrFe(CO)4, while in 1:1 ratio (Sn:Fe = 1:2) the Sn(0) complex (Httbap)Sn[Fe(CO)4]2 is formed, in which Httbap is a neutral zwitterionic form of the ligand. The structures of both bimetallic species are reported. Thermal decomposition of (Httbap)Sn[Fe(CO)4]2 under low-pressure CVD conditions gives a film containing a mixture of cubic-Sn, cubic-Fe and the hexagonal intermetallic phase Fe3Sn.