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Upstream product

• 18080-94-9 1,1-diphenylsilene 
• 75-64-9 tert-butylamine 
• 144-79-6 chloromethyldiphenylsilane 

Relevant academic research and scientific papers

Kinetics and mechanism of the addition of aliphatic amines to transient silenes

Primary and secondary amines such as n-butyl-, t-butyl-, and N,N-diethylamine add across the Si=C bond of transient silenes such as 1,1-diphenylsilene (1a) and 1,1-bis(4-trifluoromethylpenyl)silene (1b) to yield the corresponding amino(methyl)diarysilanes as the only products of reaction. The kinetics and mechanism of reaction of these three amines with the two 1,1-diarylsilene derivatives have been studied in hexane, acetonitrile, and tetrahydrofuran (THF) solution by laser flash photolysis techniques, using the corresponding 1,1-diarylsilacyclobutanes as photochemical precursors to the silenes. The reactions proceed with clean second-order kinetics and bimolecular rare constants in excess of 5 × 108 M-1 s-1 in hexane and MeCN, with 1b being up to four times more reactive than 1a. Arhenius plots for reaction in hexane and/or acetonitrile solution show strong curvature over the 0-60°C temperature range, consistent with an addition mechanism involving the intermediacy of a zwitterionic silene-amine addition complex, which collapses to product by intramolecular proton transfer from nitrogen of the silenic carbon. The reactions are substantially slower in THF, where rate reductions on the order of 5-10-fold and 50-70-fold are observed for 1a and 1b, respectively, as compared to MeCN solution. This is due to the effects of complexation of the silenes with the ether solvent, the equilibrium constant for which enters the expression for the reaction rate constant in the complexing solvent. In contrast to the situation in hexane and MeCN. Arrhenius plots for reaction of n-BuNH2 wth 1a,b in THF solution are linear and lead to positive activation energies. Addition of amines in THF solution is proposed to occur predominantly via the free silenes but with minor contributions from a pathway involving nucleophilic displacement of the solvent from the silene-solvent complex.

THE REGIOSELECTIVITY OF DEPROTONATION OF UNSYMMETRICAL KETONES WITH LITHIUM TERT-BUTYLTRIALKYLSILYL AMIDES

The regioselectivity of deprotonation of 2-methylcyclohexanone, 2-heptanone, phenylacetone, 4-methyl-2-pentanone, trimethylsilyl acetone and 3-methyl-2-pentanone with the lithium salt of the readily prepared t-BuNHSiR3 amines, where the silyl group is tri

Indirect Nuclear Spin-Spin Coupling Constants of Nitrogen-15 to Silicon-29 in Silylamines

The 15N-29Si spin-spin coupling constants in silylamines have been measured from 29Si satellites in their natural abundance 15N n.m.r. spectra in an INEPT sequence for accumulation of signals and interpreted in terms of Fermi-contact interaction; the sensitivity of 1J(15N-29Si) to d?-p? bonding was noted.