Methyl- -amine. photolysis

Tuazon et al. (1984a) investigated the atmospheric reactions of TV-nitrosodimethylamine and dimethylnitramine in an environmental chamber utilizing in situ long-path Fourier transform infared spectroscopy. They irradiated an ozone-rich atmosphere containing A-nitrosodimethyl-amine. Photolysis products identified include dimethylnitramine, nitromethane, formaldehyde, carbon monoxide, nitrogen dioxide, nitrogen pentoxide, and nitric acid. The rate constants for the reaction of fV-nitrosodimethylamine with OH radicals and ozone relative to methyl ether were 3.0 X 10 and <1 x 10 ° cmVmolecule-sec, respectively. The estimated atmospheric half-life of A-nitrosodimethylamine in the troposphere is approximately 5 min. 

Heterocyclic Chemistry (CHEC-I). Reactivity of 1,3,2-dithiazole-5-ones, -thiones, -imines, and 1,3,2-oxathiazole-5-ones is also much more widely covered than in CHEC-I, their thermolysis, photolysis, oxidation, methylation, amination, hydrolysis, 1,3-cycloaddition, etc. are discussed. 

TABLE 20. Photolysis (x 224-194 nm) of methyl amine in the gas phase (226) (100 torr, room temperature). Quantum yields are based on the hydrogen bromide actinometer. 

The photolysis of 2 -azido-2,4,4, 6-tetramethylbiphenyl (47) in diethylamine gives 10% of a mixture of A,iY-dicthyl-4-methyl-7-mesityl-3//-azcpin-2-amine (48) and the isomeric 3H-azepine 49, together with the unexpected 4//-azepine SO as the major product." Formation of the 4//-azepine is attributed to severe steric interactions in all conformers of the 3H-tautomers. 

Base-catalyzed loss of hydrogen fluoride from the initially formed //../V-diethylG-ltrifluoro-methyl)-3//-azepin-2-amine (66) to give iV,ALdiethyl-3-(difluoromethylene)-3//-azepin-2-amine (67) occurs on photolysis of 2-(trifluoromethyl)phenyl azide (65) in diethylamine.10... 

Photolysis of methyl 4-azidobenzoate in a 1 % solution of diethylamine in methanol affords only /V,iV-dicthyl-3//-azepin-2-amine (50% yield), a result which emphasizes the superior nucleophilic character of diethylamine in these reactions.199... 

In the photolysis of methyl-(3,5,5-trialkyl-3,5-dihydro-[l,2,3]triazol-4-ylidene)-amine (34) in solution, aziridine imines are formed quantitatively, about 85% on the non-least-motion path and 15% on the least-motion path (90CB2195). The gas-phase pyrolysis of 34 affords only the product of the former path (93CB2683). 

Solid-state photolysis of salt crystals of a-mesitylacetophenone-/ -carbox-ylic acid 55 and optically pure amines such as (S)-( — )-phenylethylamine or ( R,2S)-( —)-norephedrine caused 8-hydrogen abstraction from the methyl group, and then cyclization to produce the corresponding 2-indanol derivative 56 in excellent yield and high enantiomeric excess (Scheme 12) [68]. 

Photolysis of the aryl-alkyl azide CH CPhaNa showed that the migratory aptitudes of the methyl and phenyl groups were almost identical and this and the formation of triphenylmethyl amine from irradiation of triphenylmethyl azide in the presence of efficient hydrogen donors were taken to confirm the existence of discrete nitrene intermediates. Although the occurrence of a triplet-sensitized decomposition from alkyl azides and triphenylmethyl azides (the... 

The photolysis of quinone derivatives with secondary amines was presumed to involve an aziridine derivative as an intermediate. The photochemical reaction of 3-chloro-2-bis(ethoxycarbonyl)methyl-l,4-naptho-quinone (246) with 6-(4-bromophenyl)-3,6-diazabicyclo[3.1.0]hexane (247) gave aziridinopyrrolo[l,2-fl]benz[/]indoloquinone (248) as a model compound of mitomycin by a one-pot reaction in 63% yield (Scheme 44). ... 

The formation of pyrroles by the photolysis of furan or thiophene in the presence of a primary amine was considered to involve valence-bond isomers of pyrroles but the latter were not isolated. However, the photoreaction of cyanopyrrole was examined at the same time as that of cyanofuran (Section I,A), and much earlier than that of cyanothiophenes (Section I,B). Irradiation of 2-cyano- 1-methylpyrrole in methanol was reported to give l-cyano-3-methoxy-5-methyl-5-azabicyclo[2.1.0]pentane, which may have been formed from the Dewar compound (Eq. 14).4 The structure of the... 

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