Dienes as possible intermediates in the catalytic hydrogenation of aromatic hydrocarbons. 1. Dienes derived from 1,4-di-tert-butylbenzene and a rhodium catalyst
Dienes as possible intermediates in the catalytic hydrogenation of aromatic hydrocarbons. 1. Dienes derived from 1,4-di-tert-butylbenzene and a rhodium catalyst
NbCl<sub>3</sub>-catalyzed [2+2+2] intermolecular cycloaddition of alkynes and alkenes to 1,3-cyclohexadiene derivatives
作者:Yasushi Obora、Keisuke Takeshita、Yasutaka Ishii
DOI:10.1039/b820352k
日期:——
NbCl3(DME)-catalyzed [2+2+2] intermolecular cycloaddition of alkynes and alkenes was successfully achieved to give 1,4,5-trisubstituted-1,3-cyclohexadiene derivatives in good yields.
Wavelength effect on the photochemical reactions of (z)-2,5-dimethyl-1,3,5-hexatrene: selective excitation of rotamers
作者:A.M. Brouwer、J. Cornelisse、H.J.C. Jacobs
DOI:10.1016/s0040-4020(01)89975-0
日期:1987.1
5-hexatriene 1 is typical of a cZt triene, but the long wavelength tail Indicates the presence of the (minor) cZc rotamer. The sudden change In the photoreactivity of 1 around 290 nm is in agreement with selective excitation of these rotamers. No indication is obtained for an intrinsic excitation energy dependence of the photoreactivity of the Individual rotamers.
Photochemistry of 2,5-dialkyl-1,3,5-hexatrienes. The influence of the ground-state conformation, controlled through steric substituent effects
作者:A. M. Brouwer、L. Bezemer、J. Cornelisse、H. J. C. Jacobs
DOI:10.1002/recl.19871061203
日期:——
The photochemical reactions of a number of 2,5-dialkyl-1,3,5-hexatrienes are described. Variations in the selectivity of the reactions are observed, which can be rationalized by considering differences in the composition of the equilibrium mixture of conformational isomers, brought about by stericsubstituenteffects. This result is in agreement with the NEER principle. In addition, examples are given