2650-50-2Relevant academic research and scientific papers
Spectroscopic evidence for an intramolecular C-H···N hydrogen bond: Infrared and Raman spectroscopy and ab initio molecular orbital calculations of N,N-dimethylpropylamine and propyltrimethylammonium bromide
Ohno, Keiichi,Tonegawa, Akimitsu,Yoshida, Hiroshi,Matsuura, Hiroatsu
, p. 219 - 228 (1997)
The infrared and Raman spectra were measured for N,N-dimethylpropylamine (DPA) in an argon matrix, the liquid and glassy states and aqueous solution, and for propyltrimethylammonium bromide (PTAB) in the solid state and aqueous solution. The ab initio molecular orbital calculations were performed on possible conformers of DPA and propyltrimethylammonium ion. In an argon matrix, the conformational stability of DPA is in the order G'G > GT > TT, which agrees with the prediction by ab initio calculations. The experimentally confirmed high stability of the G'G conformer indicates that an appreciably strong attractive interaction occurs between the methyl hydrogen atom and the nitrogen atom. This interaction may be called the intramolecular 1,4-C-H···N hydrogen bonding. In the liquid and glassy states, the GT conformer is the most stable. In aqueous solution of DPA, the GT and TT conformers are more stabilized than in the neat liquid, possibly because of the formation of more significant intermolecular hydrogen bonds between the nitrogen atom of DPA and water molecules. For PTAB, only the T conformer exists in the solid state, and this conformer is more stable than the G conformer in aqueous solution. The GG and TG conformers of DPA and the G conformer of PTAB are significantly less stabilized by steric repulsions between the CH3(N) and (C)CH3 groups.
Odd-even effect and unusual behavior of dodecyl-substituted analogue observed in the crystal structure of alkyltrimethylammonium-[Ni(dmit) 2]- salts
Dai, Kotaro,Nomoto, Kuniharu,Ueno, Shinji,Tomono, Kazuaki,Miyamura, Kazuo
experimental part, p. 312 - 319 (2011/05/13)
A series of [Ni(dmit)2]- (dmit: 1,3-dithiole-2- thione-4,5-dithiolato) salts of alkyltrimethylammonium (Cn: n represents the alkyl chain length; n = 3 and 518) have been prepared and analyzed by X-ray structural analysis. All complex salts have been found to be composed of alternate sheets of [Ni(dmit)2]- anions and sheets of cations with a pronounced interdigitation of the alkyl chains. However, molecular arrangement differed between (C3)[Ni(dmit)2] and other (Cn)[Ni(dmit)2] (n = 518). Adjacent cations were aligned along the long axis of [Ni(dmit)2]- anion in C3 complex salt, while in others (C5-C18 complex salts), they were aligned toward the short axis. Such a difference in arrangement arose from correlativity between the lengths of the long axis of cation and anion, namely CLCA. Furthermore, relative orientation between the alkyl chain of cation and [Ni(dmit)2]- anion differed between the odd- and even-numbered cations for C10-C18. Whereas the plane of alkyl chain for odd-numbered cation was normal to the plane of [Ni(dmit)2]- anion, that of even-numbered cation was parallel. It was also found that C12 analog behaved like odd-numbered cations. However, in C12 salt, the end methyl group of the dodecyl group adopted unusual end-gauche conformation.
Solubilization of some Tetramethylammonium Salts and of Ethyltrimethylammonium Bromide by their Homologues in Chloroform
Czapkiewicz, Jan
, p. 2669 - 2674 (2007/10/02)
The solubilities of tetramethylammonium chloride, bromide, thiocyanate and perchlorate and of ethyltrimethylammonium bromide in chloroform at 25 +/- 0.2 deg C have been determined.The solubilities of these salts increase markedly in the presence of a variety of higher homologues of common co-ions.It is suggested that this phenomenon involves the cooperative formation of reversed micelles.
