Reduction of azides to amines mediated by tin bis(1,2-benzenedithiolate)

[reaction: see text] A procedure for the conversion of azides to amines, which uses NaBH4 and catalytic amounts of tin(IV) 1,2-benzenedithiolate, is disclosed. Primary, secondary, tertiary, aromatic, and heteroaromatic azides are reduced in excellent yields under very mild conditions.     

Reduction of chromium in ethylene polymerisation using bis(imido)chromium(VI) catalyst precursors

Hybrid density functional calculations on [Cr(NR)2C3H7(C2H4)]+ (R = H, tBu) have revealed a facile reductive elimination reaction involving beta-hydrogen transfer from the alkyl chain, suggesting that the active species in ethylene polymerisation with bis(imido)chromium(VI) precursors contains a reduced chromium atom.     

Hexafluorosilicates of bis(carboxypyridinium) and bis(2-carboxyquinolinium)

The preparation and characterization of three isomeric carboxypyridinium and carboxyquinolinium hexafluorosilicate salts is described. The salts of the general formulas (LH)₂[SiF₆] (I-III, L = 2-carboxypyridine, 3-carboxypyridine, 4-carboxypyridine) and (LH)₂[SiF₆]·2H₂O (IV, L = 2-carboxyquinoline) were prepared from the protonation reaction of the corresponding pyridine carbonic acid by the fluorosilicic acid. The compounds were characterized by IR, mass-spectrometry, thermogravimetric analysis, solubility data, and in the case of III by X-ray crystallography. The relationship between the salts solubility and the H-bonding system was analysed.     

Synthesis and characterization of sodium bis(trimethylstannyl) amide and bis(trimethylsilyl) bis(trimethylstannyl) -phospha-tetrazene

Sodium bis(trimethylstannyl)amide NaN(SnMe₃)₂, isolated by the reaction of trimethylstannyldiethylamine with sodium amide, reacts with tris(trimethylsilyl)hydrazino—dichloro-phosphine to form bis(trimethylsilyl)bis(trimethylstannyl)-2-phospha-2-tetrazene, (Me₃Si)₂N-N=P-N(SnMe₃)₂. Both the molecules have been isolated and characterized.     

Reduction of carbodiimides by samarium(II) bis(trimethylsilyl)amides-formation of oxalamidinates and amidinates through C-C coupling or C-H activation

The reaction of [Sm{N(SiMe3)2}2(THF)2] (THF=tetrahydrofuran) with carbodiimides RN=C=NR (R=Cy, C6H3-2,6-iPr2) led to the formation of dinuclear SmIII complexes via differing C-C coupling processes. For R=Cy, the product [{(Me3Si)2N}2Sm(micro-C2N4Cy4)Sm{N(SiMe3)2}2] (1) has an oxalamidinate [C2N4Cy4]2- ligand resulting from coupling at the central C atoms of two CyNCNCy moieties. In contrast, for R=C6H3-2,6-iPr2, H transfer and an unusual coupling of two iPr methine C atoms resulted in a linked formamidinate complex, [{(Me3Si)2N}2Sm{micro-(RNC(H)N(Ar-Ar)NC(H)NR)}Sm{N(SiMe3)2}2] (2) (Ar-Ar=C6H3-2-iPr-6-C(CH3)2C(CH3)2-6'-C6H3-2'-iPr). Analogous reactions of RN=C=NR (R=Cy, C6H3-2,6-iPr2) with the SmII "ate" complex [Sm{N(SiMe2)3Na] gave 1 for R=Cy, but a novel C-substituted amidinate complex, [(THF)Na{N(R)C(NR)CH2Si(Me2)N(SiMe3)}Sm{N(SiMe3)2}2] (3), for R=C6H3-2,6-iPr2, via gamma C-H activation of a N(SiMe3)2 ligand.     

Synthesis of bis(glycosylamino)alkanes and bis(glycosylamino)arenes

The condensation of D-mannose and D-galactose with aliphatic and aromatic diamines afforded a series of bis(glycosylamino)alkanes and-arenes. A possible mechanism was proposed for the formation of 1,2-bis(β-D-glycosylamino)benzenes. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2793–2801, December, 2005.     

Molecular structure and bonding properties of bis(1-methylimidazole)bis(perchlorato)bis(pyridineN-oxide)copper(II)

Summary The crystal and molecular structure of bis(1-methylimidazole)bis(perchlorato)bis(pyridineN-oxide)copper(II) have been determined using three-dimensional x-ray diffraction data. The complex crystallizes in space group P2₁/c with Z=2. The cell dimensions area=9.355(3),b=14.363(4),c=9.698(4) Å, and =106.40(3)^o. Least-squares refinement of the structure has yielded a final R value of 0.049 for 1235 independent reflections. The centrosymmetric structure consists oftrans pairs of 1-methylimidazole and pyridineN-oxide figands forming a square planar geometry with Cu–N and Cu–O bond lengths of 1.963(4) Å and 1.948(4) Å, respectively. The two perchlorate ions are located above and below the square plane with Cu–O distances of 2.590(5) Å. The uv-vis and i.r. spectra and bonding properties of the title compound are discussed with reference to the structure.     

Synthesis of volatile bis[bis(trimethylsilyl)amide]-substituted boron derivatives

Russian Journal of General Chemistry - General strategy for the synthesis of organoboron compounds containing bis(trimethylsilyl)amide substituents has been suggested.