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1

Synthesis and Rearrangement of 2-(N-Methyl-N-nitroamino)-4-phenylthiazole

Spaleniak G., Daszkiewicz Z., Kyzio J.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 2

171-178

EN

2-(N-Methyl-N-nitroamino)-4-phenylthiazole (5) was prepared and rearranged in aqueous dioxane under influence of sulphuric acid of various concentrations. 2-(N-Methylamino)- 5-nitro-4-phenylthiazole (6) was the only product up to 50% acid concentration. At higher acidities, significant amounts of nitro derivatives 3b and3c, substituted in benzene ring, were also formed. The result indicates that migration of the N-nitro group occurs on the intramolecular path, however, in concentrated sulphuric acid, formation of nitronium ion and ring nitration also takes place.

2

Concomitant Rearrangement of [15N-NO@}-N-(4-Fluorophenyl)-N-methylnitramine and N-Methyl-N-phenylnitramine

Daszkiewicz Z., Kyzioł J. B.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 9

1217-1220

3

Structure and Rearrangement of Ring Substituted N0Methyl-N-phenylnitramines

Daszkiewicz Z., Zaleski J., Nowakowska E. M., Kyzioł J. B.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 8

1113-1125

EN

The mechanism of the acid catalyzed nitramine rearrangement must account for the unusual sensitivity of the reaction of N-methyl-N-phenylnitramine derivatives to the ring substituents. Spectral analyses indicate the lack of interaction between the nitramino group and the second substituent through the aromatic ring. X-ray analyses confirm the spectral data: there is no conjugation between the aromatic and nitramine sextets of _-electrons. X-ray structural data also indicate that the nitramino group cannot behave as the basic centre. A reconsideration of the rearrangement rate constants of the series of ring substituted N-methyl-N-phenylnitramines lead to the conclusion that migration of the N-nitro group precedes protonation. The influence of the substituents on the reaction rates is determined by their influence on the basicity of the imino nitrogen in an intermediate. The CIDNP effect, observed in the rearrangement, results from the transformation of mobile nitrito group into the stable nitro substituent.

4

Dipole Moment, Molar Kerr Constant, Crystal and Molecular Structure of 3-Chloro-N-methyl-N-nitroaniline

Prezhdo V., Bykova A. S., Głowiak T., Prezhdo O. V., Daszkiewicz Z., Kyzioł J. B.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 5

707-718

EN

Dipole moment, molar Kerr constant, crystal and molecular structure of m- ClC6H4N(CH3)NO2 (or C7H7ClN2O2) are studied. Comparison the data obtained by dipole moment and molar Kerr constant measurement, X-ray crystallographic investigation and quantum-chemical calculation show that the molecule contains a planar NNO2 nitroamino group which is twisted around the N-Cphenyl bond by ca 61.4_ from the plane of the aromatic ring. The structural data are compared with the data for p- ClC6H4N(CH3)NO2 and the influence of the substituent on the structural parameters of the molecule is established.

5

Tetrakisphenol

Nowakowska E., Daszkiewicz Z., Kyzioł J.B.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 7

1191-1197

EN

Formylation of bisphenol-A (1a), with subsequent methylation, oxidation and esterification, gave 2,2-bis-(4-methoxy-3-methoxycarbonylphenyl)-propane (11b). It was transformed into 2,2-bis-[4-methoxy-3-(2-hydroxy-2-propyl)-phenyl]-propane (12b) by the addition of methylmagnesium iodide. The carbinol was condensed with phenol in the presence of dry hydrogen chloride and the title compound was isolated as its tetramethyl ether (4b). Its structure of 2,2-bis-[4-hydroxy-3-(4-hydroxycumyl)-phenyl]-propane (4a) was confirmed by (13)C-NMR spectra. In PhOH/HCL medium tetrakisphenol (4a) decomposed and isomerized to bisphenol-A (1a).