Electrolytic methoxylation of 3,4-bis(hydroxymethyl) furan and synthesis of 4,5-bis-(hydroxymethyl) pyridazine

3,4-Bis(hydroxymethyl)furan was electrolytically methoxylated during intense cooling. 4,5-Bis(hydroxymethyl)pyridazine was obtained by reaction of the methoxylation product — 2,5-dimethoxy-3,4-bis (hydroxymethyl)-2,5-dihydrofuran — with hydrazine hydrate.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1306–1307, October, 1970.     

Reaction of 2-chloro-5-methylbenzoquinone with Β-aminocrotonic ester derivatives

The reaction of 2-chloro-5-methylbenzoquinone with -aminocrotonic ester derivatives was studied by PMR spectroscopy in CD₃COOD. The spectra indicate the formation of intermediate hydroquinone and quinone derivatives, which subsequently transform into the corresponding indoles. It was shown that the indolization proceeds unequivocally at the 3-position of the initial benzoquinone, and the rate of formation of the indole derivatives decreases with increase in the size of the substituent at the nitrogen atom of the -aminocrotonic ester. The starting, intermediate compounds and the end products observed in the PMR spectra were identified by comparison with specially synthesized compounds.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 324–328, March, 1990.     

Electronic regioselectivity in the reactions of pyridinium ylides with tetracyanoethylene

Highly regioselective reactions of pyridinium ylides with tetracyanoethylene occur via an Ad_N-E mechanism to form Z-isomers of 3-aroyl-3-(1-pyridinio)-1,1,2-tricyano-2-propenides-1, corresponding in structure to 1,4-ylides with maximum charge separation. If the unsaturated nitrite starting material contains a nucleofugal group 1,2-elimination predominates over 1,3-elimination.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1087–1094, August, 1991.     

Synthesis of substituted 3-thiophenecarbaldoximes containing unsaturated groups at C2

A convenient preparative method was developed to obtain substituted 2-allylthio-5- methyl-3-thiophenecarbaldoximes, which are starting compounds in the synthesis of fused heterocycles containing the thiophene ring, by the successive action of sodium in liquid ammonia and substituted -halopropenes on 2-methylthio-5-methyl-3-thiophenecarbaldoxime.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, PP. 247–251, January, 1991.     

Laboratory and Industrial Applications of Microwave Techniques

The use of microwave techniques in scientific research is reviewed. Also some semicommercial-scale microwave units are examined.