Magnetic Resonance in Chemistry 2007-04-01

Synthesis and structure of some azo coupled cyclic beta-enaminones.

Petr Simůnek, Lucie Lusková, Markéta Svobodová, Valerio Bertolasi, Antonín Lycka, Vladimír Machácek

Index: Magn. Reson. Chem. 45(4) , 330-9, (2007)

Full Text: HTML

Abstract

The reaction of 3-phenylaminocyclopent-2-en-1-one with 4-methyl, 4-methoxy and 4-chlorobenzenediazonium tetrafluoroborates was used to prepare the azo coupling products 3a-c. It was found that these compounds are present in both CDCl(3) solution and solid phase practically exclusively as (E)-3-phenylamino-2-(4-subst.phenyldiazenyl)cyclopent-2-en-1-ones with N--H...N intramolecular hydrogen bond. The substitution of the phenyl residue of the diazonium salt has no effect on the position of the tautomeric equilibrium. On the other hand, the compounds 4a, b formed by the reaction of 3-phenylamino-1H-inden-1-one with 4-methylbenzene- or benzenediazonium tetrafluoroborates exist in CDCl(3) solution and in solid phase as hydrazone compounds. In the solution they occur as a mixture of three forms, out of which two were identified as E/Z isomers with different types of hydrogen bonds. Compound 5 formed by the reaction of 3-amino-5,5-dimethylcyclohex-2-en-1-one with 4-methoxybenzenediazonium tetrafluoroborate is converted into a stable hydrochloride 5.HCl on standing in CHCl(3) solution; this product exhibits a high degree of delocalization of the positive charge. Its structure was studied by means of X-ray.


Related Compounds

Related Articles:

Photoluminescence imaging of solitary dopant sites in covalently doped single-wall carbon nanotubes.

2015-12-28

[Nanoscale 7 , 20521-30, (2015)]

Electronic properties of Si surfaces and side reactions during electrochemical grafting of phenyl layers.

2006-01-26

[J. Phys. Chem. B 110(3) , 1332-7, (2006)]

EPR and spin-trapping investigation of free radicals from the reaction of 4-methoxybenzenediazonium tetrafluoroborate with melanin and melanin precursors. Reszka KJ and Chignell CF.

[J. Am. Chem. Soc. 115(17) , 7752-60, (1993)]

More Articles...