TY - JOUR
T1 - Photolysis of nitroso-compounds. Part IV. 1-Chloro-1-nitrosocyclohexane and other geminal chloro-nitroso-compounds
AU - Gowenlock, Brian G.
AU - Pfab, Josef
AU - Kresze, Günther
PY - 1974
Y1 - 1974
N2 - Detailed studies of the photolysis of 1-chloro-1-nitrosocyclohexane are presented. Photolysis in methanol solutions gave hydrochloric acid, methyl nitrite, 1,1-dimethoxycyclohexane, cyclohexanone, and cyclohexanone oxime. 1-Methoxycyclohexene and 6-hydroxyimino-1-methoxycyclohexene were minor products. Photolysis in aprotic solvents afforded 1-chlorocyclohexene, cyclohexanone, and 1,1-dichlorocyclohexane with small amounts of a-chlorocyclohexanone and 1-chloro-1-nitrocyclohexane at low concentrations whereas at high concentrations substantial amounts of cyclohexanone oxime were found. Evidence based on the variation of product distribution with solvent, concentration, and added radical scavengers is presented, which shows that the primary photochemical step consists in C-NO bond cleavage in all solvents. a-Chloronitrones are postulated as intermediates. The importance of solvolysis and other secondary ionic reactions is emphasised. Other studies of the photolysis of geminal chloronitrosoadamantane, 3-chloro-3-nitrosopentane, and 2-chloro-2-nitrosobutane in alcohols are briefly re-examined in the light of the proposed mechanism. In none of these cases have we found any evidence for a carbonyl-like photoreduction.
AB - Detailed studies of the photolysis of 1-chloro-1-nitrosocyclohexane are presented. Photolysis in methanol solutions gave hydrochloric acid, methyl nitrite, 1,1-dimethoxycyclohexane, cyclohexanone, and cyclohexanone oxime. 1-Methoxycyclohexene and 6-hydroxyimino-1-methoxycyclohexene were minor products. Photolysis in aprotic solvents afforded 1-chlorocyclohexene, cyclohexanone, and 1,1-dichlorocyclohexane with small amounts of a-chlorocyclohexanone and 1-chloro-1-nitrocyclohexane at low concentrations whereas at high concentrations substantial amounts of cyclohexanone oxime were found. Evidence based on the variation of product distribution with solvent, concentration, and added radical scavengers is presented, which shows that the primary photochemical step consists in C-NO bond cleavage in all solvents. a-Chloronitrones are postulated as intermediates. The importance of solvolysis and other secondary ionic reactions is emphasised. Other studies of the photolysis of geminal chloronitrosoadamantane, 3-chloro-3-nitrosopentane, and 2-chloro-2-nitrosobutane in alcohols are briefly re-examined in the light of the proposed mechanism. In none of these cases have we found any evidence for a carbonyl-like photoreduction.
UR - http://www.scopus.com/inward/record.url?scp=37049128048&partnerID=8YFLogxK
M3 - Article
SP - 511
EP - 518
JO - Journal of the Chemical Society, Perkin Transactions 2
JF - Journal of the Chemical Society, Perkin Transactions 2
SN - 1472-779X
IS - 5
ER -