Study on Cis-trans Isomerization in Diene Rubbers during Vulcanization

Kinetics of the cis,cis to trans,trans isomerization of 1,1,2,2,5,5,6,6-octamethyl-1,2,5,6-tetrasilacycloocta-3,7-diene.

The kinetics of the ruthenium-promoted cis,cis to trans,trans isomerization of 1,1,2,2,5,5,6,6-octamethyl-1,2,5,6-tetrasilacycloocta-3,7-diene were investigated. Incubation of a ruthenium alkylidene complex, (Cy(3)P)RuCl(2)(==CHPh)Ru(p-cymene)Cl(2), in CD(2)Cl(2) for 5 days at 40 degrees C afforded a catalytically active ruthenium species that was shown to be responsible for promoting the isome...

Trans-cis isomerization and the blue phases.

A new class of photoactive chiral liquid crystals based on a photoactive nematic host material and a photoinactive chiral dopant was utilized to investigate the behavior of the blues phases when trans-cis isomerization is induced. While the general behavior follows what has been observed in the cholesteric phase, the sensitivity of the blue phases to external parameters causes different behavio...

Density functional theory study of the trans-trans-cis (TTC)-->trans-trans-trans (TTT) isomerization of a photochromic spiropyran merocyanine.

Density Functional Theory (DFT) calculations have been performed on the TTC-->TTT isomerization reaction of the open forms of the 1',3'-dihydro-8-bromo-6-nitro-1',3',3'-trimethylspiro[2H-1-benzopyran-2,2'-(2H)indole (8-Br-6-nitro-BIPS) system. The calculations were carried out in vacuo and in methylene chloride solution at different temperatures. Results are compared with the available experime...

A New Family of Styrene/Diene Rubbers

Electron transfer mediated geometrical cis-trans isomerization of polyenes

In view of the possible role of electron transfer in biology and medicine, and wide distribution of polyenes in living nature, we consider the electron transfer mechanism of geometrical cis-trans isomerization as an important route which can play a key role in many photochemical and biological processes. The various mechanisms of geometrical cis-trans isomerization mediated by electron transfer...