RESUMEN
trans-Dibromobis(5-tert-butylpyrazole-N(2))copper(II), trans-[CuBr(2)(Hpz(tBu))(2)] (Hpz(tBu) is 5-tert-butylpyrazole, C(7)H(12)N(2)), exhibits a distorted square-planar geometry with a significant tetrahedral twist, while trans-dibromotetrakis(5-tert-butylpyrazole-N(2))copper(II), trans-[CuBr(2)(Hpz(tBu))(4)], adopts a distorted octahedral geometry across a crystallographic inversion centre. Both compounds exhibit intramolecular N--H...Br hydrogen-bonding interactions.
RESUMEN
The title compound, [Cu(C27H40BN6)2]*2CH2Cl2, contains a four-coordinate Cu(II) ion lying on a crystallographic inversion centre, giving rise to a near-regular square-planar stereochemistry. There is an axial contact of 2.71 A between the Cu ion and ligand B-H group, although this is unlikely to correspond to a significant 'agostic' interaction.
RESUMEN
The title compound, C(9)H(10)Br(2)O, is a major product of the radical bromination of 4-methoxy-1,2-dimethylbenzene. Each Br atom is involved in a close contact with the O atom of a neighbouring molecule, forming a geometry that is suggestive of weak intermolecular O--> Br charge-transfer interactions.
RESUMEN
Thermolysis in the solid state of Cs+[arachno-CB9H14]-, or of Cs+[nido-CB9H12]-, or the oxidation of nido-1-CB8H12 with I2 in THF at -78 degrees C in the presence of NEt3, gives the first nine-vertex closo monocarbaborane, the stable [closo-4-CB8H9]- anion, in yields of 56, 61 and 75%, respectively.
RESUMEN
B10H14 and PhCHO yield [6-Ph-nido-6-CB9H11]- (94%), from which the nine-vertex C-phenyl monocarbaborane anion [4-Ph-closo-4-CB8H8]- (68%) can be obtained by heating at 200 degrees C, and from which the twelve- and ten-vertex analogues [1-Ph-closo-1-CB11H11]- (50%) and [4-Ph-closo-4-CB9H9]- (25%) can be obtained by heating at 210 degrees C with BH3(NEt3).