High-pressure alkylation of azomethines

Reaction of anils with alkyl halides under high pressure (10 kbar) was studied. Alkylation in polar media (dioxane or acetonitrile) followed by hydrolysis yields pureN-monoalkylamines in high yields. Optimum conditions for high-pressure alkylation were found.     

Synthesis of N-(2-pyridyl)cyanoacetamides and 4-amino-2H-pyrido-[1,2-a]pyrimidin-2-ones from ethyl cyanoacetate and 2-aminopyridine

The reaction of 2-aminopyridine and 2-aminopicolines with ethyl cyanoacetate under high pressures results in the formation of 4-amino-4H-pyrido[1,2-a]pyrimidin-2-ones. Depending on the structure of the initial pyridine base, heating of a mixture of the above reagents under low vacuum gives either the same products or their isomeric N-(2-pyridyl)cyanoacetamids. The mutual transformations of the synthesized isomers were studied; it was found that cyanoacetamides are readily cyclized by the action of an alcoholic solution of HCl into pyrido[1,2-a]pyrimidin-2-ones, while the latter, during sublimation or heating in DMSO, undergo opening of the pyrimidine ring.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2107–2113; September, 1990.     

Trimerization of perfluoroheptanonitrile at high pressures

Conclusions A study was carried out on the trimerization of perfluoroheptanonitrile under high pressure conditions at 110 and 124°C. This reaction obeys zero-order kinetics relative to the monomer and first-order kinetics relative to the catalyst.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1893–1895, August, 1987.     

Synthesis of tetrazoles by the reaction of furan and thiophene nitriles with organic azides under high pressure

Conclusions The reactions of furan and thiophene nitriles with organic azides under high pressure yielded compounds containing tetrazolefuran and tetrazolylthiophene fragments.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 461–463, February, 1985.     

Stereochemically controlled synthesis of racemic sitophilate,the aggregational pheromone of the grain weevil

Controlled condensation of propionaldehyde with Li- or Si-enolates, generated from sec-amyl propionate, readily afforded a mixture of diasteromeric 2-methyl-3-hydroxypentanoic acid 3-pentyl esters, which were easily separated by chromatography. The erythro-isomer is the racemic form of the major component (sitophilate) of the aggregational pheromone of the grain weevil, a harmful granary pest. Beilis-Hillman condensation of propionaldehyde with sec-amyl acrylate under high pressure and subsequent hydrocuprination or hydrozirconation of the intermediate adduct afforded the (±)-sitophilate in an overall yield of >35%.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 807–811, April, 1990.     

High-pressure initiated synthesis of dominicalures 1 and 2 by the Baylis-Hillman method

The dimerization of methyl acrylate to dimethyl -methyleneglutarate by the action of tributylphosphine in the absence of a solvent was investigated. Methyl -methylene--hydroxypentanoate was obtained with a moderate yield by the condensation of propionaldehyde with methyl acrylate catalyzed by triphenylphosphine or 1,4-diazabicyclo[2.2.2]octane and initiated by high pressure. In the last of these data a three-stage stereospecific synthesis of dominicalures 1 and 2 (components of the aggregation pheromone of the grain beetle) was realized from sec-amyl acrylate and propionaldehyde or isobutyraldehyde.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 595–599, March, 1990.     

Effect of high pressure on hydrogen atom detachent by tert-butoxy radicals

Conclusions Increasing the pressure increases the rate of H atom detachment in hydrocarbon substitution by tertbutoxy radicals, the increase being the more pronounced the higher the rate constants for the reaction at atmospheric pressure. N. D. Zelinskii Institute of Organic Chemistry, Academy of Sciences of the USSR, Moscow. Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2201–2204, October, 1976.