A study of the OH- -induced beta-elimination reactions of 2-(4-chloroethyl)pyridine, 2-(2-chloroethyl)pyridine, 1-methyl-2-(4-chloroethyl)pyridinium iodide and 1-methyl-2-(2-chloroethyl)pyridinium iodide in acetonitrile/water

Second-order rate constants have been determined for the title reactions in OH(-)/H(2)O and in OH(-)/ (CH(3)CN/H(2)O) [30/70, 60/40, and 85/15 (v/v) mixtures]. A relatively small increase in reactivity is observed for the four substrates upon increasing the percentage of CH(3)CN in the solvent mixture. The methyl activating factors (/) are also slightly affected by the solvent composition. On the other hand, the high acceleration of the reaction by methylation of the pyridine ring amounts to 10(4)-10(6) according to an E1cb mechanism.     

Synthesis and study of 1-(2-pyrimidinyl)-1H-pyrazolo[3,4-b]pyridine derivatives

New 1-(2-pyrimidinyl)-1H-pyrazolo[3,4-b]pyridine derivatives were obtained. The reactivity in reactions involving nucleophilic substitution of the chlorine atom by amino, arylamino, and hydrazino groups was investigated. Data from the IR, UV, and PMR spectra are presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 963–967, July, 1981.     

Kinetics and mechanism of the reaction of 1-benzoyloxy-4-[4-(dimethylamino)styryl]pyridinium tetrafluoborate with trimethyl-benzylammonium chloride in acetonitrile

The reaction of 1-benzoyloxy-4-[4-(dimethylamino)styryl]pyridinium tetrafluoborate with trimethylbenzylammonium chloride in acetonitrile takes place with the formation of an ion pair of 1-benzoyloxy-4-[4-(dimethylamino)styryl]pyridinium chloride, the slow decomposition of which to the σ adduct is rate-determining. The equilibrium constants of the individual steps of formation of ions from the ionogens PhCOCl and DASPO are determined. L. M. Litvinenko Institute of Physical Organic Chemistry and Carbon Chemistry, National Academy of Sciences of Ukraine, 70 Lyuksemburg ul., Donetsk 341114, Ukraine. Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 34, No. 3, pp. 148–152, May–June, 1998.     

Structure of [UO2Cl4]2- in acetonitrile

The complex formation of uranyl UO(2)(2+) with chloride ions in acetonitrile was studied by UV-vis and U L(III) EXAFS spectroscopy. The investigations unambiguously point to the existence of a [UO(2)Cl(4)](2-) species in solution with D(4)(h)() symmetry. The distances in the U(VI) coordination sphere are U-O(ax) = 1.77 +/- 0.01 Angstroms and U-Cl = 2.68 +/- 0.01 Angstroms.     

Synthesis of 4-(2-chloroethyl)-2,3-dihydro[1,4]oxazino[2,3-b]quinoline and 4-(2-chloroethyl)2,3-dihydropyrido[2,3-b][1,4]oxazine

The title compounds were synthesized from 3-[bis(2-hydroxyethyl)amino]quinolin-2(1H)-one 11a and 3-[bis(2-hydroxyethyl)amino]pyridin-2(1H)-one 18 respectively. The preparation involved a tandem chlorination/cyclization reaction.     

Kinetic and thermodynamic interpretation of the reversible reaction of 2,4,6-trinitrochlorobenzene with 4-[4-(dimethylamino)styryl]pyridine in acetonitrile

The energetic and activation parameters for the reversible reaction of 2,4,6-trinitrochlorobenzene with 4-[4-(dimethylamino)styryl]pyridine in acetonitrile were determined. The rate constants for the forward and reverse reactions were found to be equal at 300 K. L. M. Litvinenko Institute of Physical Organic and Coal Chemistry, National Academy of Sciences of Ukraine, R. Lyuksemburg St., 340114 Donetsk. Ukraine. Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 33, No. 3, pp. 149–152, May–June, 1997.     

Kinetic and mechanistic studies of the interaction of 2-mercapto pyridine with dichloro[1-alkyl-2-(arylazo)imidazole]palladium(II) complexes

Nucleophilic substitution of Pd(RaaiR′)Cl₂ [(RaaiR′ = 1-alkyl-2-(arylazo)imidazole, p-R-C₆H₄-N=N-C₃H₂NN-1-R′; where R = H(a)/ Me(b)/ Cl(c) and R′ = Et(1)/Bz(2)] with 2-Mercaptopyridine (2-SH-Py) in acetonitrile (MeCN) at 298 K, to form [Pd₂(2-S-Py)₄], has been studied spectrophotometrically under pseudo-first-order conditions and the analyses support the nucleophilic association path. The reaction follows the rate law, Rate = {k ₀ + k [2-SH-Py] ₀ ² }[Pd(RaaiR′)Cl₂]: first order in Pd(RaaiR′)Cl₂ and second order in 2-SH-Py. The rate of the reaction follows the order: Pd(RaaiEt)Cl₂ (1) < Pd(RaaiBz)Cl₂ (2) and Pd(MeaaiR′)Cl₂ (b) < Pd(HaaiR′)Cl₂ (a) < Pd(ClaaiR′)Cl₂ (c). External addition of Cl⁻ (LiCl) and HCl suppresses the rate (Rate ∝ 1/[Cl⁻]₀ & ∝1/[HCl]₀). The reactions have been studied at different temperatures (293–308 K) and activation parameters (Δ^‡ H° and Δ ^‡ S°) of the reactions were calculated from the Eyring plot and support the proposed mechanism.     

Synthesis and reactivity with M(II) (M=Co and Cu) chloride of 1-[(2-carboxyethyl)benzene]-3-[benzothiazole]triazene

Reaction of ethyl anthranilate, sodium nitrite, and 2-aminobenzothiazole produces a new triazenide compound, 1-[(2-carboxyethyl)benzene]-3-[benzothiazole]triazene (HL), which has been characterized by X-ray crystallography and NMR spectrum. In the presence of Et₃N, reaction of HL and CuCl₂?·?2H₂O or CoCl₂?·?6H₂O in THF/methanol affords a tetranuclear copper(II) complex [Cu₄L₄(µ-OMe)₄]?·?4THF (1) and a cobalt(III) complex [CoL′₃] (2) (L′ is 1-[benzothiazole] triazene ion), accompanied by C–N bond cleavage of HL. They are characterized by X-ray crystallography and magnetic susceptibility measurement. Magnetic studies indicate significant antiferromagnetic coupling between the copper(II) centers for 1. The value obtained for the coupling constant J is ?585?cm^?1.