Sulphones photoisomerization

Numerous photorearrangements and related transformations have been described in the period covered by this Report. Reversible interconversion of two rotational isomers of methyl thionitrite has been detected in an argon matrix at 12K, and the cis-form of iV-methylthioacetamide was generated photo-chemically, at low temperatures in inert-gas matrices, from the much more stable trans-thioamide. Triplet-sensitized Z,E-photoisomerizations of /3-styryl methyl sulphone and 3-(4-cyanostyryl) methyl sulphone have been examined, and various (Z)-P-styryl methyl sulphones (200) have been prepared by irradiation of the corresponding E-isomers (201). Z,E-Photoisomerization of 2-naphthylvinylenethioamide has been examined in... 

Direct irradiation of 9-dimethylsulphonium fluorenylide (141) in acetonitrile or tetrahydrofuran yields primarily the Stevens rearrangement product 9-methyl-9-(methylthio)fluorene (142), and a 1,2-shift of a sulphonic acid group is thought to be involved in the photoisomerization of the sodium salt of metanilic acid (m-aminobenzenesulphonic acid). Photoinduced rearrangement of 4,5-(ethylenedithio)-1,3-dithiole-2-thione (143) to the... 

I- cis- and 7,13-di-ciy-isomers of vitamin A [retinol (91)] have been prepared via the 1-cis photoisomerization product of the sulphone (94).62 Several isotopically labelled species of retinaldehyde and derivatives have been synthesized, including... 

Liquid crystalline azobenzene polymers can undergo photoisomerization on irradiation at 360 or 450 nm on gold films. This permits changing the refractive index of the film depending upon the wavelength used136. A study has examined the photopolymerization of p-styrene sulphonate counteranions associated with monolayers of disulphide amphiphiles as self-assembled monolayers on gold137. 

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See also in sourсe #XX -- [ ]

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