1103586-08-8Relevant academic research and scientific papers
Complex thermal behavior of 11-cis-retinal, the ligand of the visual pigments
Lopez, Carlos Silva,Alvarez, Rosana,Dominguez, Marta,Faza, Olalla Nieto,De Lera, Angel R.
, p. 1007 - 1013 (2009)
Upon heating to 80 °C, 11-cis-retinal yields a mixture of all-trans-retinal and 13-cis-retinal. This isomerization has been studied by means of density functional theory methods, and the computational results suggest a close competition between two mechanisms of very different nature. A classical internal rotation around the C11-C12 cis double bond, via a diradical transition state, accounts for the formation of the all-trans isomer. An intricate sequence of pericyclic reactions, namely a reversible [1,7]-H sigmatropic shift and a reversible 6-π-oxa-electrocyclic reaction, is responsible for the formation of 13-cis-retinal. Experiments using 11-cis-retinal labeled with deuterium at C19 confirmed the mechanistic proposal and also revealed an unprecedented outcome on the product composition of isotopologues.
