ISSN:
0009-2940
Keywords:
Thiophene fulgide anthrylvinyl, synthesis and E/Z isomerizations of
;
Photochromism
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Preparation and Photochemistry of an Anthrylvinyl Thiophene FulgideThe base-catalyzed reaction of isopropylidenesuccinate 2 with phenylthienylpropenone 1a does not give a Stobbe condensation to 3a but results in an 1,4-addition to 7 which under the basic conditions reacts further to 8 by an intramolecular condensation. The (anthrylvinyl)thiophene fulgide 4c is obtained, however, from 3-glyoxyloyl-2,5-dimethylthiophene hydrate (11) via the 2H-pyran 14: Wittig olefination of 14 with the phosphonium salt 16 leads to the diester 3c which easily is converted to Z,E-4c. - Irradiation of Z,E-4c gives a mixture of all four possible E,Z isomers of 4c and the ring-closed valence tautomers Z- and E-17. All isomers could be separated and characterized. Compound 18, formed irreversibly in a thermally-induced reaction, is enriched during irradiation.
Additional Material:
5 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19921251133
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