ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
α-Methylthio-propiophenone anti-oxime p-toluenesulfonate (tosylate) (12b) fragments quantitatively in 80% ethanol yielding benzonitrile and a methylidenesulfonium ion 15. The syn-isomer, however, undergoes a Beckmann rearrangement. The fragmentation of α-methylthio-isobutyropher one anti-oxime tosylate (13b) is accompanied by cyclization to the 1, 2-thiazetin-1-ium ion 27, which is hydrolyzed via the sulfimine 29 to the keto sulfide 20 and the keto sulfoxide 30. A comparison of the rates of the α-alkylthio anti-ketoxime tosylates 12b and 13b and of the homomorphous oxime tosylates 16b and 17b shows that fragmentation and cyclization are strongly assisted by the sulfur atom. Whereas both the anti- and syn-isomers of α-amino ketoxime derivatives fragment quantitatively, only the anti-isomers of α-alkylthio ketoxime derivatives undergo facile fragmentation.
Additional Material:
2 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19740570833
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