The mutual influence of ligands in transition metal bis-chelates

Electronic structure quantum chemical calculations of the Fe(II), Ni(II) and Cu(II) bis-chelate series are reported. The nature of the ligand mutual influence effect on these compounds is elucidated. This effect manifests itself in polarization of metal—ligand bonds. The ligands which have highly covalent bonds with the metal form bonds of even greater covalent character in mixed complexes, whereas bonds for the other ligands become more ionic.     

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.     

Pyrrolo[2,1-b]benzothiazole derivatives

A new method for obtaining pyrrolobenzothiazole derivatives, which can be used for the specific synthesis of polymethine dyes with predesignated properties, was developed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 549–553, April, 1991.     

Condensation of aryl bromides with styrenes,catalyzed by nickel complexes in the presence of zinc

Conclusions Condensation of aryl bromides with styrenes in acetonitrile in the presence of nickel organometallic complex catalysts and metallic zinc occurs regio- and stereoselectively to give E-stilbenes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2508–2511, November, 1987.     

Reaction of 5-chloroanthra[1,9-cd]-6-isoxazolone with oxygen-containing nucleophiles

Facile nucleophilic substitution of the chloride ion to give 5-alkoxy- or 5-aryloxy-anthra[1,9-cd]-6-isoxazolones occurs in the reaction of 5-chloroanthra[1,9-cd]-6-isoxazolone with alcohols and phenols. The possibility of conversion of the synthesized isoxazolones to 1-amino-4-alkoxyanthraquinones is demonstrated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1329–1331, October, 1983.