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1

The lightfastness and structure of semi-permanent hair dyes, derivatives of o-nitro-N-β-hydroxyethylaniline

Szuster Lucjan, Wojciechowski Krzysztof, Rutowicz Joanna

Technologia i Jakość Wyrobów

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2023

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R. 68

19--37

EN

The aim of this study was to examine the substituent effects on lightfastness and spectral properties of o-nitro-N-β-hydroxyethylaniline derivatives, used in semi-permanent hair dyes of HC (Hair Color-Dyes ) type. It has been found that the fading rate of the color of hair dyed depends on the nature of the ED and EA substituents in the o-nitro-N-β-hydroxyethylaniline. The o-nitro-N-β-hydroxyethyl aniline derivatives undergo discoloration according to kinetics of the first order reaction. A negative value of the slope coefficient indicates the oxidative mechanism of the reaction. From the relationship lmax=f(σ) σp─Hammett’s constant were calculated. Using the semi-empirical AM1 quantum chemical method, we calculated the structures of hair dyes The dye structures were optimized using MM +, DM, and AM1.

PL

Celem pracy było zbadanie wpływu podstawników na działanie światła i właściwości spektralne pochodnych o-nitro-N-β-hydroksyetyloaniliny, stosowanych w półtrwałych farbach (semi-permanent) do barwienia włosów. Stwierdzono, że szybkość zaniku barwy włosów zależy od charakteru podstawników ED i EA w o-nitro-N-β-hydroksyetyloanilinie. Pochodne o-nitro-N-β-hydroksyetyloaniliny ulegają odbarwieniu zgodnie z kinetyką reakcji 1-go rzędu. Ujemna wartość współczynnika nachylenia wskazuje na mechanizm utleniający reakcji. Z zależności lmax=f(σ) obliczono stałe σp─Hammetta. Stosując półempiryczną metodę kwantowo-chemiczną AM1, obliczyliśmy budowę barwników pochodnych N-β-hydroksyetyloamino-nitrobenzenu. Struktury barwników optymalizowano przy użyciu MM +, DM oraz AM1. półtrwałe farby do włosów.

2

A neural-network controlled dynamic evolutionary scheme for global molecular geometry optimization

Styrcz A., Mrozek J., Mazur G.

International Journal of Applied Mathematics and Computer Science

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2011

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Vol. 21, no 3

559-566

EN

A novel, neural network controlled, dynamic evolutionary algorithm is proposed for the purposes of molecular geometry optimization. The approach is tested for selected model molecules and some molecular systems of importance in biochemistry. The new algorithm is shown to compare favorably with the standard, statically parametrized memetic algorithm.

3

Crystal and molecular structure of 3-(2,4,6-trimethyl-phenyl)-8-phenyl-oxo-1,7-dioxa-2-azaspiro[4,4]non-2-ene

Anulewicz-Ostrowska R., Piętka E., Krygowski T., Micuch P., Fisera L.

Polish Journal of Chemistry

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1999

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vol. 73 nr 4

727-733

EN

Crystal and molecular structure of 3-(2,4,6-Trimethylphenyl)-8-phenyl-oxo-1,7-dioxa-2-azaspiro[4,4]non-2-ene has been determined by X-ray diffraction technique. Crystal data for C21H21NO3: monoclinic, C2/c, a=20.969(4) A, b=10.319(2) A, c=16.601(3) A, b=97.5(3)0, Z=8, R=0.0658 for 3477 reflections. Contrary to the solution, in the crystalline state only one conformer exists.

4

Crystal and Molecular Structure of 1,3,5-Trimethoxy-2,4,6-trinitrobenzene : Mesomeric Effects for Out-of-plane Twisted Substituents

Anulewicz-Ostrowska R., Krygowski T., Cyrański M., Matuszewska M.

Polish Journal of Chemistry

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1999

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Vol. 73, nr 11

1895-1901

5

Comparison of the ab-initio calculated and X-ray molecular geometries of the o-, m-, and p-cyanoaniline

Janczak T.

Polish Journal of Chemistry

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1999

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vol. 73 nr 4

655-667

EN

Ab-initio gas-phase structure calculation of the geometry of three isomers of the cyanoaniline were determined using the Hartree-Fock level of theory. The optimized molecular structures have been compared with the in-crystal geometry of the molecules. The small differences in the bond lengths and angles were interpreted and analyzed in terms of the distribution of the charge density. The calculated charge density and its Laplacian function were analyzed in terms of the topological properties at the (3,-1) critical points (CPs) of the covalent and polar bonds. The effect of the donor-/acceptor functional groups attached to the phenyl ring is demonstrated especially in the location of the bond critical points and in the charge density at the bond critical points.

6

The crystal and molecular structure of cyclic thioamide beta-dikotone derivatives. Intramolecular H-bonding and the problem of quasiaromaticity

Anulewicz R., Krygowski T.M., Jagodziński T.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 2

439-448

EN

Crystal and molecular structures of the 2,6-dioxocyclohexanethiocarboxanilide (I), 4,4-dimethyl-2,6-dioxocyclohexanethiocarboxanilide (II) and 1,3-indandione-2- thiocarboxanilide (III) have been determined by use of X-ray diffraction technique on a Kuma-diffractometer. Crystal data for compound (I): C13H13N1O2S1, M-r=247.32, monoclinic, C2/c, a=22.704(5)A, b=7.312(1)A, c=17.192(3)A, beta=123.07(3), Z=8, R=0.0597 for 2181 reflections. Compound (II): C15H17N1O2S1, M-r=275.36, triclinic, P-1, a=10.748(1)A, b=9.223(2)A, c=7.346(2)A, alpha=91.21(3), beta=100.36(3), gamma=76.01(3), Z=2, R=0.0733 for 2485 reflections. Compound (III): C16H11N1O2S1, M-r=281.12, triclinic, P-1, a=6.945(3)A, B=8.786(1)A, c=12.435(3)A, alpha=86.97(3), beta=73.78(3), gamma=66.74(3), Z=2,R=0,0696 for 2361 reflections. Of the two potentially H-bonding systems of each of the title compounds one that with OH...S, is stronger and this resilts in a stronger pi-electron delocalization. This is quantitatively measured by HOMA index, which is by ca. 0.3 units larger than for the other H-bonding system, the one with the NH...O bridge.