Nitrosamine aliphatic

Aldehydes or Ketones with Other Functional Groups Aldehydes, Ketones with Other Functional Groups Kepone Chlordecone Aliphatic Flydrocarbons Aliphatic Nitriles and Cyanates Acetonitrile Acrylonitrile Aliphatic Nitriles Aliphatic Nitrosamines Aliphatic Nitrosamines A-Nitrosodimethylamine (NDMA)... 

The reaction is generally thought to involve carbonium-ion intermediates but several puzzling features remain. Secondary aliphatic amines give nitrosamines without evolution of N2 ... 

Tertiary aliphatic amines react in the cold to give nitrite salts and these decompose on warming to give nitrosamines and alcohols ... 

The nitrosation of oximes can also serve to produce N-hydroxy-N-nitrosamines (Scheme 3.9). The acidified nitrite procedure can be applied to oximes derived from terpenes [132] and hydroxyguanidine [133] for the synthesis of N-hydroxy-N-nitrosamines. However, some a, 5-uri saturated oximes were converted into pyrazole-1,2-dioxides [134]. The alkyl nitrites under basic conditions have produced interesting results. Quinone dioximes yielded only monodiazeniumdiolates [135], while simple aliphatic oximes gave products resulting from addition to the imine double bond... 

N-Hydroxy-N-nitrosamines with an aliphatic group at O2 produce a compound stable to aqueous acid and base (Fig. 3.4, 29) [158], whereas all other N-hydroxy-N-nitrosamines are susceptible to hydrolysis and appropriate 02-derivatives also render these materials vulnerable. The hydrolysis endpoint is the formation of nitroxyl (HNO) [which dimerizes to form nitrous oxide (N20)] and a C-nitroso compound. These products are formed from aryl [159] and alkyl bound unsubstituted diazenium-diolates as well as Oralkylated derivatives [160]. Studies of the solvolysis of Oi-alkyl derivatives are complicated by their tendency to decompose via competing radical pathways [161], but the Oi-benzyl derivatives are unique in that they hydrolyze back to the original synthetic precursors (Scheme 3.14) [162]. 

As detailed by Gatehouse and Tweats (1987), the nature and concentration of solvent may have a marked effect on the test result. Dimethysolphoxide is often used as the solvent of choice for hydrophibic compounds. However, there may be unforeseen effects, such as an increase in mutagenicity of some compounds, for example, / -phcnylenediamne (Burnett et al., 1982) or a decrease in mutagenicity of others, such as simple aliphatic nitrosamines (Yahagi et al., 1977). It is essential to... 

The main feature in the PE spectra of aliphatic nitrosamines45,133-138 are two very distinctive bands in the region 8.5-10.0 eV which are assigned to a 7r-type orbital 7r2 mainly localized on the amino nitrogen atom and an no orbital. IPs of some nitrosamines are summarized in Table 14. 

A laboratory-assembled supercritical fluid extractor was designed for the efficient recovery of volatile nitrosamines from frankfurters. The nitrosamines were separated and detected using a GC-TEA-CLD. Recovery of 10 volatile aliphatic and alicylic nitrosamines from frankfurters spiked at the 20 ppb level was 84.3-104.8% with RSD 2.34-6.13%581. 

Pitts, J.N., Jr., Grosjean, D., Cauwenberghe, K.V., Schmid, J.P., and Fitz, D.R. Photooxidation of aliphatic amines under simulated atmospheric conditions formation of nitrosamines, nitramines, amides, and photochemical oxidant, Environ. Sci Technol, 12(8) 946-953, 1978. 

N-nitrosamines are a group of compounds characterized by a nitroso group (N=0) attached to the nitrogen of an aromatic or aliphatic secondary amine. N-nitrosodi-N-propylamine is a suspected reaction byproduct from the nitrosation of di-N-propylamine. Two pesticides are suspected to contain some form of nitrosamines. 

Ordinarily, alkyl nitrate esters will not nitrate amines under neutral conditions. However, Schmitt, Bedford and Bottaro have reported the use of some novel electron-deficient nitrate esters for the direct At-nitration of secondary amines. The most useful of these is 2-(trifluoromethyl)-2-propyl nitrate, which nitrates a range of aliphatic secondary amines to the corresponding nitramines in good to excellent yields. Nitrosamine formation is insignificant in these reactions. 2-(Trifluoromethyl)-2-propyl nitrate cannot be used for the nitration of primary amines, or secondary amines containing ethylenediamine functionality like that in piperazine. Its use is limited with highly hindered amines or amines of diminished nucleophilicity due to inductive or steric effects. 

Methylenediamines are readily synthesized from the reaction of secondary amines with formaldehyde. Many aliphatic amines are too basic for direct nitration without a chloride catalyst, and even then, nitrosamine formation can be a problem. Their conversion into intermediate methylenediamines before nitration is therefore a useful route to secondary nitramines. The success of these nitrolysis reactions is attributed to the inherent low basicity of the methylene-diamine nitrogens. 

Lijinsky W, Reuber MD Comparative carcinogenesis by some aliphatic nitrosamines in Fischer rats. Cancer Lett 14 297-302, 1981... 

In 1972, Eiter and his group reported the synthesis of a-alkoxy dialkyl N-nitrosamines (11),which can be obtained easily in 20-50 g quantities. This synthetic scheme works well when formaldehyde was used. In those cases when higher aliphatic aldehydes are used (e.g. acetaldehyde), the yields decreased to 3-5%. The a -alkoxy dialkyInitrosamines always contained the trimeric paraldehyde as impurity. When acetaldehyde and... 

Pitts, J. N., Jr., D. Grosjean, K. Van Cauwenberghe, J. P. Schmid, and D. R. Fitz, Photooxidation of Aliphatic Amines under Simulated Atmospheric Conditions Formation of Nitrosamines, Nitramines, Amides, and Photochemical Oxidant, Enriron. Sci. Technol., 12, 946-953 (1978). 

Franchimont, Rec 16,226 8(1897) (Contribution to the knowledge of aliphatic nitramines) b) J.Pinnow, Ber 30,833-43(1897) (Aromatic nitramines and nitrosamines) c)E.Bamberger, J3er 30,1248-63(1897) (AIkylnitramines)(earlier refs are given) d)G.R.Ciemo j.M.Smith,... 

Prior to florisil column cleanup, the column should be preeluted with ether-pentane mixture (15 85 v/v). The extract is then transferred onto the column and the column is eluted again to remove ary diphenylamine contaminant. The analytes A-mtrosodnnethylanune, A-mtrosodi-n-propylamine, and A-nitrosodiphc-nylamine, and other similar aliphatic and aromatic nitrosamines are desorbed from the column with acetone-ether mixture (5 95 v/v). This fraction is then concentrated for analysis. 

Sulfanilic acid (0.5%)/a-naphthylamine (0.05%) in 30% acetic acid Spraying is preceded by short-wave UV irradiation (3 min) aliphatic nitrosamines yield red/violet spots, while aromatic ones yield green/blue spots (limit 0.2-0.5y) 1,72,73... 

Halogenated methanes Alkyl-N- nitrosamines Carbamates Aliphatic epoxides... 

Gas chromatography has been applied to the determination of a wide range of organic compounds in trade effluents including the following types of compounds which are reviewed in Table 15.15 aromatic hydrocarbons, carboxylic acids aldehydes, non ionic surfactants (alkyl ethoxylated type) phenols monosaccharides chlorinated aliphatics and haloforms polychlorobiphenyls chlorlignosulphonates aliphatic and aromatic amines benzidine chloroanilines chloronitroanilines nitrocompounds nitrosamines dimethylformamide diethanolamine nitriloacetic acid pyridine pyridazinones substituted pyrrolidones alkyl hydantoins alkyl sulphides dialkyl suphides dithiocaibamate insecticides triazine herbicides and miscellaneous organic compounds. 

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