Crystal structure of N-(β-acetoxyethyl)-4-methylpyridinium bromide

In continuation of previous studies [1] on structures of compounds differing from acetylcholine and choline by having a pyridine ring instead of the quaternary N atom, the x-ray structure of N-(-acetoxyethyl)-4-methylpyridinium bromide, which has cholinergic activity [2], is solved.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1813–1816, August, 1991.     

Synthesis of cyanamides containing the phenothiazine fragment and their reactions with dialkyldithiophosphoric acids

Reaction of phenothiazine with dialkoxyphosphoryl or chlorosulfenyl isocyanide dichlorides has given 10-cyanophenothiazine, which adds dialkyldithiophosphoric acids at the CN bond. The addition products rearrange to 10-[N-(dialkoxythiophosphoryl) thiocarbamoyl]phenothiazines, which are prone to decompose to dialkoxythiophosphoryl isothiocyanates and phenothiazine, or on treatment with alkyl halides in the presence of base afford stable S-alkyl-N- dialkoxythiophosphoryl (l0-phenothiazinyl)isothioformamides. The reaction between 10-cyanophenothiazine and an excess of dithiophosphoric acids also affords 10-thiocarbamoylphenothiazine and tetraalkyl trithiopyrophosphates. An x-ray diffraction examination of the molecular structure of S-methyl-N-diisopropoxythiophosphoryl-(10-phenothiazinyl)isothioformamide has shown it to possess the Z-configuration. The dihedral angle formed by the benzene rings of the phenothiazine fragment is 125.7°. The products of the addition of dithiophosphoric acids to the CN bond of N,N-bis[2-(10-phenothiazinyl)-2-oxoethyl]cyanamide, obtained from 10-(chloroacety) phenothiazine and NaNHCN, also isomerize by 1,3S N migration of the thiophosphoryl group. Subsequent heterocyclization, with elimination of phenothiazine, affords 2-(dialkoxythiophosphorylimino)-3-[2-(10-phenothiazinyl)-2-oxoethyl]thiazolidin-5-ones.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 451–460, February, 1991.     

A new synthetic route to chiral 3-aryl-5-ethyl-1,4,2-oxazaphosphorines

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Dinuclear complexes with bis(benzenedithiolate) ligands

As a part of a broader study directed towards helical coordination compounds with benzenedithiolate donors, we have synthesized the bis(benzenedithiol) ligands 1,2-bis(2,3-dimercaptobenzamido)ethane (H(4)-1) and 1,2-bis(2,3-dimercaptophenyl)ethane (H(4)-2). Both ligands form dinuclear complexes with Ni(II), Ni(III) and, after air-oxidation, Co(III) ions under equilibrium conditions. Complexes (NEt(4))(4)[Ni(II)(2)(1)(2)] (11 b), (NEt(4))(2)[Ni(III)(2)(1)(2)] (13), and Na(4)[Ni(II)(2)(2)(2)] (14) were characterized by X-ray diffraction. In all complexes, two square-planar [Ni(S(2)C(6)H(3)R)(2)] units are linked in a double-stranded fashion by the carbon backbone and they assume a coplanar arrangement in a stair-like manner. Cyclic voltammetric investigations show a strong dependence of the redox potential on the type of the ligand. The substitution of 1(4-) for 2(4-) on nickel (-785 mV for 11 b versus -1130 mV for 14, relative to ferrocene) affects the redox potential to a similar degree as the substitution of nickel for cobalt (-1160 mV for [Co(2)(1)(2)](2-)/[Co(2)(1)(2)](4-), relative to ferrocene). The redox waves display a markedly less reversible behavior for complexes with the shorter bridged ligand 2(4-) compared to those of 1(4-).     

Chiral recognition of N-thiophosphorylated thioureas via nickel(ii) coordination assisted by 4-dimethylaminopyridine

Nickel(ii) complexes were synthesized using chiral N-thiophosphorylated thioureas as the starting compounds and 4-dimethylaminopyridine as a co-ligand. The reaction with racemic thiourea afforded homochiral complexes due to the distortion of the nickel coordination. The unsaturated coordination sphere of nickel ions results in the formation of supramolecular homochiral 1D chains in the crystal through steric key—lock interactions between adjacent molecules. Conformational flexibility of the ligands is responsible for disorder of molecules in the crystals and the occurrence of polymorphs.

     

Chiral S‐stannyl dithiophosphates and dithiophosphonates on the basis of monoterpenols

Chiral S‐tributylstannyl dithiophosphates and dithiophosphonates were obtained by the reactions of optically active dithiophosphoric and dithiophosphonic acids containing (S)‐(–)‐menthyl and (R)‐(+)‐menthyl substituents with gaseous ammonia and tributyl chlorostannane. The reactions of chiral ammonium dithiophosphate containing (1R)‐endo‐(+)‐fenchyl substituent with tributyl chlorostannane or tetrachlorostannane result in corresponding S‐tributylstannyl dithiophosphate or tetrakis(dithiophosphato)stannane. Molecular structure of ammonium O,O‐di‐(–)‐menthyldithiophosphate was studied by X‐ray single crystal diffraction. Bactericidal activity of S‐tributylstannyl dithiophosphates was tested.     

New triamidophosphonium acetals and their condensation with resorcinol and its derivatives

A number of new acetals bearing phosphonium moieties with P-N bonds were prepared. Their condensation with resorcinols in acidic water-alcohol solutions was studied, which led to new phosphonium salts having a diarylmethane fragment.     

Silver(I) complexation of linked 2,2'-dipyridylamine derivatives. Synthetic, solvent extraction, membrane transport and X-ray structural studies

Synthesis of the 2,2'-dipyridylamine derivatives di-2-pyridylaminomethylbenzene 1, 1,2-bis(di-2-pyridylaminomethyl)benzene 2, 1,3-bis(di-2-pyridylaminomethyl)benzene 3, 2,6-bis(di-2-pyridylaminomethyl)pyridine 4, 1,4-bis(di-2-pyridylaminomethyl)benzene 5, and 1,3,5-tris(di-2-pyridylaminomethyl)benzene 6 are reported together with the single-crystal X-ray structures of 2, 3, and 5. Reaction of individual salts of the type AgX (where X = NO(3)(-), PF(6)(-), ClO(4)(-), or BF(4)(-)) with the above ligands has led to the isolation of thirteen Ag(I) complexes, nine of which have also been characterised by X-ray diffraction. In part, the inherent flexibility of the respective ligands has resulted in the adoption of a range of coordination arrangements. A series of liquid-liquid (H(2)O/CHCl(3)) extraction experiments of Ag(I) with varying concentrations of 1-6 in the organic phase have been undertaken, with the counter ion in the aqueous phase being respectively picrate, perchlorate and nitrate. In general, extraction efficiencies for a given ionophore followed the Hofmeister order of picrate > perchlorate > nitrate; in each case the tris-dpa derivative 6 acting as the most efficient extractant of the six systems investigated. Competitive seven-metal bulk membrane transport experiments (H(2)O/CHCl(3)/H(2)O) employing the above ligands as the ionophore in the organic phase and equimolar concentrations of Co(II), Ni(II), Zn(II), Cu(II), Cd(II), Pb(II) and Ag(I) in the aqueous source phase were also undertaken, with transport occurring against a pH gradient. Under the conditions employed 1 and 5 yielded negligible transport of any of the metals present in the source phase while sole transport selectivity for Ag(I) was observed for 2-4 and 6.