20583-25-9Relevant academic research and scientific papers
Stereoselective Synthesis and Diels-Alder Reactions of (Z)- and (E)-1,2-Bis(phenylthio)-1,3-butadiene
Chou, Shang-Shing P.,Sun, Der-Jen,Tai, Hai-Ping
, p. 809 - 814 (2007/10/03)
Bromination of 3-phenylthio-2-sulfolene (2) with N-bromosuccinimide gave 2-bromo-3-phenylthio-2-sulfolene (3) which was converted mainly to 2,3-bis(phenylthio)-2-sulfolene (4) by treatment with sodium phenylthiolate.Thermal desulfonylation of 4 at different temperatures in the presence of a base (DBU) yielded stereoselectively the (Z)- and (E)-1,2-bis(phenylthio)-1,3-butadiene (6).These two geometric isomers could be thermally interconverted.The Diels-Alder reactions of 6 were also investigated.Only the (Z)-diene 6a could undergo the Diels-Alder reaction; the (E)-diene 6b was in situ converted to the Z isomer before undergoing the Diels-Alder reactlon.The reaction of 6a with N-phenylmaleimide gave the cycloaddition product 7 with complete endo selectivity, but under daylight or during chromatography it readily underwent a thioallylic rearrangement to yield 8 with inversion of configuration.The cycloaddition of 6a with methyl acrylate proceeded regiospecifically, but generating a mixture of endo and exo isomers.The endo/exo ratio could be increased by using ZnCl2 as the catalyst.Key Words: 1,2-Bis(phenylthio)-1,3-butadiene; Stereoselective synthesis; Diels-Alder reactions
2-Acetyl-3-(phenylthio)-1,3-butadiene: A Novel Diels-Alder Diene and Dienophile
Chou, Shang-Shing P.,Tsai, Chung-Ying
, p. 5305 - 5308 (2007/10/02)
The title compound 3 was readily obtained by the thermolysis of 3-acetyl-4-(phenylthio)-3-sulfolene (2), which was prepared from 3-(phenylthio)-3-sulfolene (1) by Friedel-Crafts acylation.Compound 3, bearing an electron-donating phenylthio group and an el
