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Thermal behavior of poly (methyl methacrylate) was analyzed in the presence of tin (IV) chloride. Five different proportionspolymer to additivewere selected for casting films from common solvent. TG, DTG and DTA were employed to monitor thermal degradation of the systems. IR and py-GC-MS helped identify the decomposition products. The blends start degrading at a temperature lower than that of the neat polymer and higher than that of the pure additive. Complex formation between tin of additive and carbonyl oxygen (pendent groups of MMA units) was noticed in the films soon after the mixing of the components in the blends. The samples were also heated at three different temperatures to determine the composition of residues left after the expulsion of volatiles. The polymer, blends and additive exhibited a one step, two-step and three-step degradation, respectively. T0 is highest for the polymer, lowest for the additive and is either 60 o C or 70 o C for the blends. The amount of residue increases down the series (moving from blend-1 (minimum additive concentration) to blend-5 (maximum additive concentration)). For blend-1, it is 7% of the original mass whereas it is 16% for blend-5. Tmax also goes up as the concentration of additive in the blends is elevated. The complexation appears to be the cause of observed stabilization. Some new products of degradation were noted apart from those reported earlier. These included methanol, isobutyric acid, acid chloride, etc. Molecular-level mixing of the constituents and "positioning effect" of the additive may have brought about the formation of new compounds. Routes are proposed for the appearance of these substances. Horizontal burning tests were also conducted on polymer and blends and the results are discussed. Activation energies and reaction orders were calculated. Activation energy is highest for the polymer, i.e., 138.9 Kcal/mol while the range for blends is from 51 to 39 Kcal/mol. Stability zones are highlighted for the blends. The interaction between the blended parts seems to be chemical in nature.

Formal [4 + 2] cycloaddition between various 3-ethoxycyclobutanones and allyltrialkylsilanes proceeded to give 3-ethoxy-5-[(trialkylsilyl)methyl]cyclohexan-1-ones by catalysis with tin(VI) chloride. The use of allyl-tert-butyldiphenylsilane induced 1,5-hydride transfer, which gave 2-[3-(tert-butyldiphenylsilyl)propyl]-6-methyltetrahydro-4-pyrones.

Polymers having bis(cyclopentadienyl)titanacyclopentadiene units in the main chain were prepared by the polymerization of a low-valent bis(cyclopentadienyl)-titanium(II) complex, generated in situ from bis(cyclopentadienyl)titanium dichloride (Cp2TiCl2) and n-butyllithium (2 equiv), with internal diynes such as 1,4-bis(1-hexynyl)-benzene and 4,4′-bis(1-hexynyl)biphenyl. The bis(cyclopentadienyl)titanacyclopentadiene-containing polymers were subjected to the reaction with tin(IV) chloride, followed by the treatment with methyllithium to give 1,1-dimethylstannole-containing organometallic polymers in moderate yields. The stannole containing polymers are soluble in organic solvents, whose number-average molecular weight was estimated to be 2,700–2,800 by GPC. Optical and electrochemical properties of the resulting stannole-containing polymers were studied by their UV-vis spectra and cyclic voltammetric analyses, from which they were supposed to have low LUMO energy levels.

The addition of diorganyl disulfides and dimethyl diselenide to cyclohexene in the presence of tin(IV) chloride proceeded stereoselectively affording trans-adducts of 1:1 composition. No reaction occurs in the absence of tin(IV) chloride.

Following observations on remote asymmetric induction using allylstannanes, 5-benzyloxy-4-methylpent-2-enylsilanes are also found to react with aldehydes with modest levels of 1,5-induction after treatment with tin(IV) chloride. Transmetallation to give intermediate allyltin trihalides may be involved.

Ortho-aminobenzonitriles 1 react with β-ketoesters and alkyl malonates, in the presence of stoichiometric amounts of tin(IV) chloride, to give 4-aminoquinolines 2 and 4-amino-2-quinolones 3 respectively. Similarly β-enaminonitriles 7 afford 4-aminopyridines 8 and 4-amino-2-pyridones 9.

In the presence of a catalytic amount of tin(IV) species generated from tin(IV) chloride and silver perchlorate, 1-O-acetyl-D-glucose stereoselectively reacts with silyl alkoxides to give the corresponding α-glucosides in high yields.

In the presence of SnCl 4 .5H 2 O, a mixture of thiols and tetraallyltin underwent 1,4- and 1,2-addition, respectively, with the imines derived from 3-alkynals to give (Z)-1-sulfenyl-1,5-alkadien-3-ols in good yields, wherethe hydrolysis of the intermediary imino species was found to be crucial.

Pyrazolo[3,4- b]pyridines have been obtained by the condensation of 5-amino-4-cyanopyrazole, readily available by the reaction of dithioacetals with substituted hydrazines, with β-ketoesters or β-diketone in the presence of tin(IV) chloride at reflux temperature in dry toluene.

Coordination complexes of nitrosobenzene with tin and titanium tetrachlorides have been prepared and subjected to solid-state 13 C NMR spectroscopy. The absence of resonances above 160 ppm characteristic of C NO and the presence of resonances of quaternary carbons in the range characteristic of C N 2 O 2  C suggests that the cis -dimer of nitrosobenzene is acting as a bidentate donor.

Several TTF salts with tin(IV) chloride anions have been prepared: [TTF][SnR2Cl3] (R = Me and Et), [TTF]2[SnR2Cl4] (R = Cl and Ph), [TTF]3[SnR2Cl4] (R = Cl, Me, and Et), and [TTF]3.3[SnPh2Cl4]. The...

Reactions of tin(IV) chloride with Schiff bases having ONN donor systems have been investigated and on the basis of elemental analysis, IR, PMR and119Sn Mossbauer spectral studies, possible structures have been indicated for the resulting new compounds. The Schiff bases used in these studies are the condensation products of salicylaldehyde with sulphathiazole, sulphaphenazole, sulphadiazine, sulphaguanidine, 2-(p-aminobenzene sulphonamide)-4,5-dimethyl oxazole, sulphisoxazole, sulphapyridine and sulphanilamide.

1:2-complexes of tin (IV) chloride with anthranilic and methyl anthranilic acids, and 1:1-complexes with meta- and para-aminobenzoic acids have been prepared by direct interaction in suitable organic solvents. The former are molecular addition compounds while the latter are ionic complexes. Negative shifts of ν(NH) and positive shifts of ν(CO) indicate nitrogen-metal bonding in all these complexes.

An adduct of Tin(IV) trichloride (2-chloroethoxide) (A′) with 2-chloroethylalcohol(A) has been prepared. Complexes of A′ with amide, dimethylurea, dimethylsulphoxide, primary, secondary and tertiary amines and α,α′-dipyridyl have been prepared. I.R. spectra of the complexes in 4000-250 cm−1 spectral region have been examined to throw some light on their structure.

C25H22ClNSn, monoclinic, P21/c (no. 14), a = 17.8179(8) Å, b = 15.6453(6) Å, c = 17.4603(7) Å, β = 116.588(2)°, V = 4352.6(3) Å3, Z = 8, R gt(F) = 0.0297, wR ref(F 2) = 0.0681, T = 100 K.