Yu. B. Salamonov

N′-(α-acetoximinoalkyl)diazene-N-oxides and some of their transformations

Nitroso compounds of the aromatic and aliphatic series react with O-acetylalkanoylamidoximes in the presence of dibromoisocyanurate, forming the previously unknown N′-(α-acetoximinoalkyl)diazene-N-oxides, which under gaseous NH3 or oxalic acid in methanol lose the acetyl group and as a result are transformed into the previously unknown N′-(α-hydroximinoalkyl)diazene-N-oxides.

Aryl-NNO-azoxy-α-nitroalkanes

Two methods of synthesis of aryl-NNO-azoxy-α-nitroalkanes bearing either one or two reactive hydrogen atoms α to the azoxy and nitro groups are described. These methods involve protection of the latter by easily removable groupings, those used being acetoxy-methyl and acetal fragments. The regiochemical nature of the diazene oxide groupings in aryl-NNO-azoxy-α-nitroalkanes obtained by oxidation of the appropriate diazenes has been established by heteronuclear NMR and x-ray structural examination. Some of the chemical properties of these diazene oxides have been examined.

Aryl-ONN-azoxy-α,α-dinitroalkanes and some of their derivatives

Previously unknownN′-dinitroalkyl-NNO-azoxybenzenes have been prepared (by nitration ofN′-(α-hydroximino) alkyl-NNO-azoxybenzenes) and transformed to some derivatives.

N-(alkoxycarbonylmethyl)diazene-N-oxides and some of their conversions

Upon reaction of aliphatic and aromatic nitroso compounds with esters of N,N-dibromoglycine N-substituted N-(alkoxycarbonylmethyl)diazene-N-oxides are formed. The ethyl ester of (2-phenyldiazene-2-oxido)acetic acid in concentrated H2SO4 is transformed into a mixture of the monophenylhydrazide and monophenylhydrazone of monoethyl oxalate and in a solution of gaseous HCl in acetic acid into the phenylhydrazone of the acyl chloride of monoethyl oxalate.

α,α-dinitroalkyl ethers of azidoximes

Conclusions1.Some α,α-dinitroalkyl ethers of azidoximes were obtained.2.The α,α-dinitroethyl ether of acetaldehyde azidoxime when treated with electrophilic reagents is capable of converting to its more stable geometric isomer; the reverse reaction is observed under UV irradiation.

Intramolecular rearrangements in 6-acetyl-2,9-dioxa-1-azabicyclo[4.3.0]nonane series

1. When reacted with boron trifluoride etherate, the 8-carbomethoxy- and 8-chloromethyl-6-acetyl-2, 9-dioxa-1-azabicyclo[4.3.0]nonanes are respectively rearranged to the 5-carbomethoxy- and 5-chloromethyl-3-γ-acetoxypropylisoxazolines. 2. When reacted with BTE, 6-acetyl-8-phenyl-2,9-dioxa-1-azabicyclo[4.3.0]nonane is rearranged to spiro [N-acetyl-5-phenylisoxazolidine-3,2′]tetrahydrofuran.

Reaction of 2,9-dioxa-1-azabicyclo[4.3.0]nonane derivatives with boron fluoride etherate

1. The direction of the reaction of boron fluoride etherate with 6,8-disubstituted 2,9-dioxa-1-azabicyelo-[4.3.0]nonanes depends on the nature and spatial arrangement of the substitatnts. 2. The first member of a new heterocyclic system was obtained, namely a spiro(isoxazolidine-3,2′-tetrahydrofuran) derivative.

(α-Nitroalkyl)-ONN-azoxysulfones and some of their transformations

A regioselective method for the synthesis of [(α-nitroalkyl)-ONN-azoxy]alkyl- and-arylsulfones by oxidative condensation of pseudonitroles with aliphatic and aromatic sulfamides under the action of dibromoisocyanurate (DBI) was proposed. The behavior of the azoxysulfones obtained toward acids and bases as well as futher transformations of the products of acid hydrolysis into salts and halo-derivatives of nitroalkylazoxysulfones were investigated.

N-(β-hydroxyalkyl)diazene-N′-oxides and some of their transformations

Conclusions1.Regioselective methods are proposed for synthesis of N-(β-hydroxyalkyl)diazene-N′-oxides by reaction of nitroso compounds with N-(β-hydroxyalkyl)hydroxylamines or with N,N-dichloro-2-hydroxyalkylamines.2.The possibility was shown of obtaining N-β-oxo- and β-arylaminocarboxyl derivatives of diazene-N′-oxides by treatment of N-(β-hydroxyalkyl)diazene-N′-oxides with aluminum isopropylate and phenyl isocyanate respectively.

Reaction of 8-substitute d 3-phenyl-5-methyl-2-oxa-1-aza-bicyclo[3.3.0]octanes with nucleophilic reagents

1. When 5-methyl-3-phenyl-8-hydroxy-2-oxa-1-azabicyclo[3.3.0]octane is reacted with methanol and propylamme the hydroxyl group is respectively replaced by the methoxy and N-propylamine group. 2. 5-Methyl-3-phenyl-8-(N-propylamino)-2-oxa-1-azabicyclo[3.3.0]octane reacts with methyl nitroacetate and ethyl cyanoacetate without a catalyst, and with acetylacetone and acetoacetic ester in the presence of BF3 etherate as the catalyst, to give condensation products.