Abstract
A series of substituted divinylsilanes: dimethyl-distyryl-(11). Triphenyl-stryrl-(12), diphenyl-distyryl(13), have been prepared for photochemical study. The results of low conversion photolyses of the di-methyl-di-styrylsilane (11) are interpreter in terms of mechanisms for (pi)-bond isomerization which do not pass through a diradical intermediate resulting from C2-C4 carbon-carbon bridging. We have also found that di-(pi)-methane like reaction pathways for these systems are inefficient. It seems likely that the different photochemical reactivity of the di-(pi)-silanes and their carbon analogs is due to the ability of silicon to destabilize the first bridged diradical intermediate along the reaction coordinate or the transition state, 170, for a one step process in which C2-C4 bonding interactions are required. In addition, a series of 1-vinyl-2-pyridone: 1-(2-methyl-1-propenyl)-(14), 1-trans-(2-phenylethenyl)-(15), 1-trans-(1-propenyl)-(16), 1-(E-2-methyl-2-carbomethoxylethenyl)-(17), 1-(5,5,-dimethyl-3-cyclohex-2-en-1-only)-18, have been synthesized by novel sequences. The spectral and photochemical properties of these compounds, (proton and carbon nmr, uv, ir, mass spec) which contain the di-(pi)-amine moiety, have been explored. We have found that the nitrogen-vinyl carbon bond conformation in 1-vinyl-2-pyridones is governed by both electronic and steric factors with the "bisected conformer" predominating..
Krochmal, Emil (1976). A mechanistic study of heteroatom di-pi-methane systems containing silicon and nitrogen. Texas A&M University. Texas A&M University. Libraries. Available electronically from
https : / /hdl .handle .net /1969 .1 /DISSERTATIONS -508596.