Synthesis and Spectroscopic Study of Iron(III) and Copper(II) Chloride Complexes with 2-(3,3-Dimethyl-1,2,3,4-tetrahydroisoquinolylidene-1)-5,5-dimethyl-2,3,5,6-tetrahydroimidazo[2,1-a]isoquinoline-3-one (L). The Crystal Structure of L

Complexes of Fe(III) and Cu(II) chlorides with 2-(3,3,-dimethyl-1,2,3,4-tetrahydroisoquinolylidene-1)-5,5-dimethyl-2,3,5,6-tetrahydroimidazo[2,1-a]isoquinoline-3-one (L) were synthesized and studied by IR and electronic absorption spectroscopy. X-ray diffraction analysis of compound L was carried out. The molecule of L was found to crystallize in the form of cis-isomer with the proton localized on the nitrogen atom of the dihydroisoquinoline fragment.     

Crystal and Molecular Structure of Bi-1,1′-(3,3-dimethyl-3,4-dihydroisoquinoline)

Bi-1,1-(3,3-dimethyl-3,4-dihydroisoquinoline) (I) was synthesized. Its crystal structure was determined by X-ray diffraction analysis. Compound I crystallizes as isomer that is intermediate between the syn- and anti-forms with the angle of rotation between the bicyclic fragments equal to 90.1°. The N(1)=C(1) bond length is 1.276(4) ± 0.003 Å.     

Crystal Structure and Spectra of 6,7-Dimethoxy-3,3-Dimethyl-3,4-Dihydroisocarbostyril Azine

Crystal and molecular structures of 6,7-dimethoxy-3,3-dimethyl-3,4-dihydroisocarbostyril azine (I) were determined using X-ray diffraction analysis and IR and electronic absorption spectroscopy. Compound Iwas found to exist in the form of an azine isomer, in which the N=C double bonds are located outside the tetrahydroisoquinoline fragments, while the H atoms migrate toward the N(1) atoms of these moieties. Model quantum-chemical calculations were performed.     

Synthesis and Structure of the Copper(II) Nitrate Complex with 1-(3-Methyl-1-phenylpyrazol-5-onylidene-4)-3,3-dimethyl-1,2,3,4-tetrahydroisoquinoline

The complex [CuL(NO₃)₂] ? CH₃CN(I), where L is 1-(3-methyl-1-phenylpyrazol-5-onylidene-4)-3,3-dimethyl-1,2,3,4-tetrahydroisoquinoline, is synthesized and studied by X-ray diffraction and IR and electronic absorption spectroscopies. Complex I is prepared by the reaction of copper(II) nitrate crystal hydrate with L in acetonitrile. The coordination polyhedron of the Cu atom in I is a distorted (4 + 1) five-vertex polyhedron, and ligand L in the structure acts as N,O-bidentate bridge. The nitrate groups in I perform different structural functions: monodentate-terminal and anisobidentate. Structure I is composed of polymeric chains -L-Cu(NO₃)₂-L- and solvate acetonitrile molecules arranged between the chains.     

Oxidation of 1-hydrazino-3,3-dimethyl-3,4-dihydroisoquinoline. X-ray,spectroscopic, and quantum-chemical study of the structure of 3,3-dimethyl-3,4-dihydroisocarbostyryl azine

3,3-Dimethyl-3,4-dihydroisocarbostyryl azine (2) has been synthesized by oxidation of l-hydrazino-3,3-dimethyl-3,4-dihydroisoquinoline (1). The crystal and molecular structures of compound 2 were determined. It has been established that in the solid state, compound2 exists as an azine tautomer. The IR, electronic, and NMR spectral data indicate that in solution the tautomeric form of2 does not change. A possible mechanism of the oxidation of1 to2 is suggested.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2468–2474, December, 1995.The authors are grateful to Professor V. F. Zakharov (Russian University of People's Friendship) for recording the¹H NMR spectra.     

1-(Cyano[benzimidazole-2-yl])methylene-3,3-Dimethyl-1,2,3,4-Tetrahydroisoquinoline: Synthesis,Structure, Spectral Parameters

1-(cyano[benzimidazole-2-yl])methylene-3,3-dimethyl-1,2,3,4-tetrahydroisoquinoline was synthesized and studied by X-ray diffraction analysis and IR and electronic absorption spectroscopy. The model quantum-chemical calculations were performed.