Amino esters from nitroso compounds

The greatest interest in such replacements attaches to transamination and transamidation and to the various methods of forming C—N bonds by means of diazonium salts and diazo compounds. Substitution of amino for nitro groups is almost wholly restricted to o- and />-dinitro compounds and is of little importance. Preparation of a-nitroso and esters from oc-nitro esters and sodium nitrite has been discussed above (pages 431, 478 and 479). 

A method involving SPE was developed for the determination of ten A-nitroso amino acids in cured meat products. These compounds were derivatized with diazomethane followed by O-acylation of hydroxyl groups with acetic anhydride-pyridine reagent. The methyl esters and their acylated derivatives were separated by GC on a DB-5 fused silica capillary column and quantified with a TEA-CLD specific for the nitric oxide derived from the thermal denitrosation of nitrosamines recovery exceeded 75% at the 10 ppb level579. 

Although only a few hydrocarbons have been studied it appears that most of them react with OH with a rate constant of ca. 109 M-1 s 1. Methane is about 4 times less reactive than this value, and cyclopentane and cyclohexane about 5 times more reactive. Alcohols, amines, ethers, and many esters also fall in the same range. Carboxylic acids and carbonyl compounds seems to be to a certain degree less reactive. Lower reactivity is also found for the protonated forms of amines and amino acids. Direct reaction of OH with the substituent is usually unimportant except for a few cases such as thiols, where H is easily abstracted from the SH, or nitroso com-... 

Aconine, the amino alcohol, is the parent of two ester-alkaloids, aconitine (the acetate benzoate) and jesaconitine (the acetate p-methoxybenzo-ate), and differs from mesaconine, the parent of mesaconitine (the acetate benzoate), only in the A-alkyl substituent. Aconine carries an 7V-ethyl (40, 49) and mesaconine an A-methyl group these two compounds thus yield the same nitro-AT-nitroso derivative, and aconitine and mesaconitine give the same oxidation product, oxonitine (41), with elimination of the A-alkyl group. It is convenient, therefore, to combine the discussion of these closely related alkaloids. 

From To - Alkanes Cycloalkanes Alkenes Alkynes Aryls Halogen compounds Alcohols Phenols Ethers, Quinones B. and Si compounds P and 6i compounds Nitro, Nitroso, Azo, Azoxy, Hydrazo, ides Amines Organometallic Aldehydes Ketones Acids, Anhydrides, Esters Arn.des, Amidines, Nitriles Hydroky-aldehydes Amino Heterocycles Nucleosides Miscellaneous, including heterocycles... 

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