139431-74-6Relevant articles and documents
The chemistry of fumarate and maleate inhibitors with platinum hydrosilylation catalysts
Lewis, Larry N.,Stein, Judith,Colborn, Robert E.,Gao, Yan,Dong, Jun
, p. 221 - 227 (1996)
Pt(MviMvi)x (MviMvi = 1,3-divinyltetramethyl disiloxane), 1, was reacted with dimethyl fumarate to give 2. Compound 2 was investigated by 1H and 13C NMR spectroscopy which showed it to be a mono-nuclear platinum compound containing one dimethyl fumarate and one chelating MviMvi ligand. The reaction of 1 with dimethyl maleate gave 3 which was analogous13C NMR spectroscopy and extended X-ray absorption fine structure spectroscopy (EXAFS). The EXAFS analysis showed the presence of Pt-C bonds in structure to the fumarate product as shown by 1H and 13C NMR spectroscopy and extended X-ray absorption fine structure to the EXAFS analysis showed the presence of Pt-C bonds and a through space close contact between Pt and the O from the carbonyl. The NMR assignments were confirmed by comparing the NMR spectra of 2 and 3 with that of (PPh3)Pt(MviMvi), 4. Reaction of 2 or 3 with an excess of an Si-H-containing compound (either MDHDHM (MDHDHM = 1,3-bis(trimethylsiloxy)-1,3-dimethylsiloxane) or Et3SiH) gave 5 in all cases. Compound 5 contains an alkyl succinate ligand. Hydrogenation of the fumarate ligand (of 2) or of the maleate ligand (of 3) occurs by reaction with Si-H; 5 appears to be an intermediate in the hydrogenation process. The reaction between 4, dimethylmaleate, and MDHDHM also gives dimethyl succinate. Differential scanning calorimetry was used to compare the effectiveness of the inhibitors in a curable formulation composed of vinyl-stopped-polydimethyl siloxane polydimethylsiloxanemethylhydrogen-copolymer, a platinum catalyst and either a maleate or fumarate inhibitor.
