X-ray diffraction study of 6-methyl-4,6-diphenyl-2-dicyano-methylene-1,2,5,6-tetrahydronicotinonitrile

✍ Scribed by V. A. Tafeenko; Yu. T. Abramenko; A. V. Ivashchenko; K. A. Nogaeva; S. V. Medvedev

• Publisher: Springer US
• Year: 1988
• Tongue: English
• Weight: 319 KB
• Volume: 24
• Category: Article
• ISSN: 0009-3122
• DOI: 10.1007/bf00475568

✦ Synopsis

It was demonstrated by x-ray diffraction analysis that l-imino-5-methyl-3,5-diphenyl-2-cyclohexene-2,6,6-tricarbonitrile, which has been erroneously described in the literature as a l-phenylethylidenemalononitrile dimer, actually has the 6-methyl-4,6-diphenyl-2-dicyanomethylene-l,2,5,6-tetrahydronicotinonitrile structure. The latter is one of three isomers that are formed as a result of the base-catalyzed dimerization of l-phenylethylidenemalononitrile. The conformation of the unsaturated heteroring is discussed.

In an investigation of the base-catalyzed reaction of malononitrile (I) with acetophenone (II) Anderson and co-workers [I] obtained a compound, to which the 4-amino-2,6-diphenylhepta-l,3,5-triene-l,l,5-tricarbonitrile (III) structure was assigned, although this formula is not in agreement with the IR spectrometric data [i, 2]. CH2(CN) z § PhCOCH: ~ Ph(CH~)C=C(CN)-C(NHz)ffiCH-C(Ph)=C(CN)2 I II HI " ~ NH2 IN Hz CN Ph CH~ CN Nc~Cl~ Nc~C~ NCv,~C ~ C~ CH 3 CH 3 IV 7 Vl YlI VIII.