ISSN:
0009-2940
Schlagwort(e):
Matrix isolation
;
Photochemistry
;
Flash pyrolysis
;
Ylides
;
Chemistry
;
Inorganic Chemistry
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
Photochemical and Thermal Generation of Thiocarbonyl Ylides from 2,5-Dihydro-1,3,4-thiadiazoles[*]Thermolysis of thiadiazolines 2a-c yields the corresponding thiiranes 5a-c exclusively. In contrast matrix photolysis in an organic glass at 77 K or in solid Ar at 10 K allows the detection of the thiocarbonyl ylides 3a-c, which are characterized by intense UV maxima at λ ≈ 350 nm. The thiocarbonyl ylides are formed in a stepwise manner and not directly from the thiadiazolines by a simple elimination of N2. In the first step a fragmentation into the thioketones 6a-c and diazomethane occurs, followed by the generation of methylene (8) from diazomethane (7). Addition of methylene to the thioketones 6a-c finally leads to the ylides 3a-c.
Zusätzliches Material:
1 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/cber.19941271226
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