Tetrahedron p. 3275 - 3284 (1981)
Update date:2022-08-04
Topics:
Gilbert, Andrew
Yianni, Paul
The photoreactions of benzene, toluene, anisole, and benzonitrile with acrylonitrile, methacrylonitrile, and vinyl acetate, and of toluene and o- and p-xylene with maleic anhydride are described.The acrylonitriles do not react with benzonitrile but yield mixtures of ortho photocycloadducts with the other arenes.Contrary to previous findings both exo and endo stereoisomers of the ortho cycloadducts of benzene and acrylonitrile are formed: the reaction is selective towards the exo isomer but the stereoisomers from methacrylonitrile and benzene are formed with approximately equal efficiencies.Complex mixtures of regio- and stereoisomers of the ortho cycloadducts are formed between toluene and the acrylonitriles but their addition to anisole is more selective and in acetonitrile essentially only 1,2-attack of the ethylene on the arene is observed.The 2:1 photoadducts of maleic anhydride with toluene and o- and p-xylene reflect formation of two regio ortho photocycloadducts in each case.The variation in the ratios of these isomers with temperature and light intensity is interpreted in terms of the differing photolabilities of the 1:1 adducts and their reactivities towards the thermal addition of the second molecule of maleic anhydride.Vinyl acetate undergoes 1,2-cycloaddition to benzonitrile but with the other arenes, meta cycloadducts are favoured.These latter additions are specifically 2,6- with respect to toluene and anisole but there is little regioselectivity with respect to the ethylene although the 7-endo acetate of the meta cycloadduct with benzene does constitute 60percent of the reaction mixture.
View MoreContact:21-7631221 15884421033
Address:326 Science and technology,Shanghai,China
Beijing Century Richap Chemistry Co.,Ltd
Contact:+86- 010-64455497
Address:Guannan County, Lianyungang City, Jiangsu Province, China
Contact:+86-28-88523492
Address:714rooms of Time Square, Pujiang County
He Bei Shun Er Chemical Co., LTD.
Contact:86-0311-86996932/86860168
Address:No 18,North street
SHANGHAI SYSTEAM BIOCHEM CO., LTD
website:http://www.systeambc.com
Contact:86-021-58380978
Address:Building 87,Lane 669, Dong Jing Road Shanghai,P.R.China
Doi:10.1021/ja00445a038
(1977)Doi:10.1021/om049510i
(2004)Doi:10.1016/j.bmcl.2006.09.069
(2007)Doi:10.1016/j.tetlet.2019.151086
(2019)Doi:10.1021/ja00444a073
(1977)Doi:10.1016/S0008-6215(00)85464-6
(1977)