33693-57-1Relevant articles and documents
NMR Spectroscopy and Theoretical Calculations in the Conformational Analysis of 1-Methylpyrrolidin-2-one 3-Halo-derivatives
De Melo, Ulisses Zonta,Silva, Ra G. M.,Yamazaki, Diego A. S.,Pontes, Rodrigo M.,Gauze, Gisele F.,Rosa, Fernanda A.,Rittner, Roberto,Basso, Ernani A.
, p. 2111 - 2121 (2015/08/19)
This study reports the results of ab initio and density functional theory (DFT) electronic structure calculations as well as 3JHH experimental and calculated coupling constant data obtained in the investigation of the conformational equilibrium of 3-halo-derivatives of 1-methylpyrrolidin-2-one. The five-membered ring assumes an envelope conformation owing to the plane of formation of the O=C-N-R bond, with C4 forming the "envelope lid". When the conformation changes, the "lid" alternates between positions above and below the amide plane. The α-carbonyl halogen assumes two positions: a pseudo-axial and a pseudo-equatorial. In the gaseous phase, the calculations indicate that the pseudo-axial conformer is more stable and preferable going down the halogen family. Natural bond orbital analysis showed that electronic delocalization is significant only for the iodo derivative. In the other derivatives, the electrostatic repulsion between oxygen and the halogen determines the conformational equilibrium. When the solvated molecule was taken into account, the pseudo-equatorial conformer population increased with the relative permittivity of the solvent. This variation was strong in the fluoro derivative, and the preference was inverted. In the chlorine derivative, the two populations became closer in methanol and acetonitrile. In the bromine and iodine derivatives, the percentage of pseudo-equatorial conformer increased only slightly owing to the dipole moment of the conformation: the pseudo-equatorial conformation has a greater dipole moment and thus is stable in media with high relative permittivity.
PRODUCTION METHOD OF HETEROCYCLIC MERCAPTO COMPOUND
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Page/Page column 47, (2008/06/13)
A method of the invention industrially produces heterocyclic mercapto compounds useful as raw materials or intermediates in the synthesis of medicaments or pesticides, or as permanent wave agent, with a high yield and high productivity using easily available starting materials. A heterocyclic mercapto compound represented by Formula (1) (wherein X represents any structure of -O-, -S-, -NH-, and -NR1-; R1 represents any of an alkyl group, alkoxy group and alkoxyalkyl group each having 1 to 6 carbon atoms; Y represents an oxygen atom, a sulfur atom or -NR2-; R2represents a hydrogen atom or alkyl group having 1 to 6 carbon atoms; and Z1 represents a divalent organic residue having at least one mercapto group) is produced by reacting a metal sulfide or a metal hydrosulfide with a compound represented by Formula (2) (wherein X and Y are as defined in Formula (1); and Z2 represents a divalent organic residue having at least one halogen group) in the presence of a solvent at a pH of 7.0 to 11.0.
HAIR PROCESSING AGENT AND METHOD FOR PERMANENT WAVING HAIR
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Page/Page column 117, (2008/06/13)
Provided are hair processing agents capable of permanent waving hair even at a neutral to weakly acidic pH range that causes less irritation to the skin, and hair processing agents in which an unpleasant odor is masked. Hair processing agents contain at least one compound represented by the formula (2). Hair processing agents contain a compound of the formula (2) and at least one compound (ii) selected from thioglycolic acid, thiolactic acid, cysteine, acetylcysteine, cysteamine, acylcysteamine, salts thereof and ester derivatives thereof. Hair processing agents contain a compound of the formula (2), a surfactant and water, and are emulsified. Hair processing agents contain a compound of the formula (2) and a specific perfume. wherein X is a structure selected from -O-, -S-, -NH- and -NR1-; R1 is an alkyl group of 1 to 6 carbon atoms; Y is an oxygen atom or a sulfur atom; in the formula (1), Z is a divalent organic residue having at least one mercapto group; in the formula (2), R is a divalent organic residue optionally having a mercapto group; and R2 is a hydrogen atom or an alkyl group of 1 to 6 carbon atoms.
