67590-88-9Relevant academic research and scientific papers
The mechanism of the photocyclization of 1,4-diarylbutenynes into aryl-substituted aromatics. The influence of amines and oxygen
Arendonk, R. J. F. M. van,Violet, Ph. Fornier de,Laarhoven, W. H.
, p. 256 - 262 (2007/10/02)
The formation of a 1,2,4-cyclohexatriene derivative (cf.7) from the singlet-excited cis-butenyne is thought to be the primary reaction step in the photocyclization of 1,4-diarylbutenynes.This very reactive intermediate can yield the end-product along various pathways: (i) directly via a hydrogen shift; (ii) via radical intermediates, formed either by acceptance of a hydrogen atom from the solvent (e.g. benzene, hexane) or by release of a hydrogen atom in the presence of oxygen; (iii) via ionic intermediates, formed either by acceptance of a proton (e.g. from methanol) or by release of a proton in the presence of amines.The rates of the cyclization are approximately equal for various butenynes.Differences in product quantum yields are mainly due to differences in the rates of the ring-opening reaction of the cyclic allene.Using laser flash photolysis two transients of the cyclization could be observed.The effects of amines on the transients is described.
ETUDE DE L'EFFET LASER DANS UNE NOUVELLE FAMILLE DE COMPOSES ORGANIQUES PRESENTANT UNE TRIPLE LIAISON : LES 1-4-DIARYL-BUT-1-EN-3-YNES
Violet, Philippe Fornier de
, p. 361 - 366 (2007/10/02)
Fluorescent properties and laser action of 1-4-diaryl-but-1-en-3-ynes derivatives are studied.Laser action has been observed between 402 and 432 nm.Correlation between laser action and substituents effects on the level of the excited states of the aryl group has been checked.The yield of laser action has been respectively found to be on the order 25percent and 5percent using respectively picoseconds or repetitive nanoseconds pulse irradiation.The results are discuss as a function of the position of the substituant, triplet-triplet absorption and photoisomerisation process.
