Heteroallene Insertions into Tin(II) Alkoxide Bonds.

A series of iso-carbamate complexes have been synthesized by the reaction of [Sn(OPr)] or [Sn(OBu)] with either aryl or alkyl isocyanates, ONC-R (R = 2,4,6-trimethylphenyl (Mes), 2,6-diisopropylphenyl (Dipp), isopropyl (Pr), cyclohexyl (Cy) and -butyl (Bu)). In the case of aryl isocyanates, mono-insertion occurs to form structurally characterized complexes [Sn{κ--R-NC(OPr)O}(μ-OPr)] (: R = Mes, : R = Dipp) and [Sn{κ--R-NC(OBu)O}(μ-OBu)] (: R = Mes, : R = Dipp). The complicated solution-state chemistry of these species has been explored using H DOSY experiments.

Tin(II) Ureide Complexes: Synthesis, Structural Chemistry, and Evaluation as SnO Precursors.

In an attempt to tailor precursors for application in the deposition of phase pure SnO, we have evaluated a series of tin (-) ureide complexes. The complexes were successfully synthesized by employing ,'-trialkyl-functionalized ureide ligands, in which features such as stability, volatility, and decomposition could be modified with variation of the substituents on the ureide ligand in an attempt to find the complex with the ideal electronic, steric, or coordinative properties, which determine the fate of the final products. The tin(II) ureide complexes - were synthesized by direct reaction [Sn{NMe}] with aryl and alkyl isocyanates in a 1:2 molar ratio.

Aerosol-assisted CVD of SnO from stannous alkoxide precursors.

The stannous alkoxides [Sn(OR)] [R = i-Pr, t-Bu, C(Et)Me, CHPh, CPh] have been synthesised by reaction of Sn(NR') with two equivalents of HOR [R' = Me, R = i-Pr; R' = SiMe, R = t-Bu, C(Et)Me, CHPh, CPh]. Single crystal X-ray diffraction analysis of the bis(diphenylmethoxide) (4) and bis(triphenylmethoxide) (5) species have shown them to comprise three-coordinate Sn(ii) centres through dimerisation in the solid state with the alkoxide units adopting transoid and cisoid configurations across the {SnO} cores respectively. Thermogravimetric analysis indicates clean decomposition and some evidence of volatility at temperatures >200 °C for all three aliphatic alkoxides, whereas both the diphenyl- and triphenylmethoxide compounds provide higher decomposition temperatures and, for the triphenylmethoxide derivative, a residual mass consistent with the formation of a carbon-containing residue.

Expanding coverage: maintain a role for the individual market.

When most Americans think about health insurance, their frame of reference is employer- or government-sponsored health plans. But individual health insurance differs from these models. Most importantly, while individual insurance provides protection against unexpected medical expenses, it is limited in its ability to subsidize the expenses of people who already have serious health conditions when they enter the market.