No abstract

The crystal and molecular structures of the title compounds, [AuCI{NH (CH,CH,NH,),}]CI[ CIO,] (1 ) and [AuCI-{N(CH,CH,NH,),}][CIO,] (2) have been determined by Patterson and Fourier methods. Compound (1 ) crystallizes in the monoclinic space groupP2Jn with four molecules in a cell of dimensions : a = 8.590( 6), b = 12.745(8), c = 12.256(8) A, and p = 113.6(1)". Compound (2) crystallizes in the orthorhombic space group P2, 2, 2, , with four molecules in a unit cell of dimensions: a = 12.976( 8), b = 10.029(7), and c = 8.171 (6) A. Anisotropic

No abstract

No abstract

Palladium(ll), platinum(ll), and gold(ll1) species react with di-2-pyridyl ketone (dpk) to give complexes in which one or two ligand molecules in the original keto-or in a newly formed diolic form are co-ordinated to the metal cation, namely: [PdCl,(dpk.HX)] [X = OH ( l ) , OMe (2), or OEt (3)] ; [PdCl,(dpk)], (4) ; [Pd(dpk* H20),] [CIO,],, (5) ; [PtCl,(dpk)], (6) ; [AuC12(dpk.H20)1CI, (7) ; and [Au(dpk*H,O),] [C104]3, (8). In solution, all species undergo either addition or release of the protic molecules depending upon the HX concentration ; the rates of reversible hydrolysis and the stability of the hydrated species increase going from PtII to PdII to Au"I thus paralleling both the electron-withdrawing properties of the metal cations and their ability to fill the apical position of a tetragonal-pyramidal co-ordination shell. The crystal and molecular structures of ( 1) and ( 7) have been determined by X-ray diffraction: (1) crystallizes in the tetragonal space group P4, with Z = 4, a = 10.597(8), and c = 11.468(9) A ; (7) crystallizes in the monoclinic space group P2Jc with Z = 4, a = 10.398( 10), b = 7.249(8), c = 18.406(12) A, and p = 91.6(8)". The structures were solved by Patterson and Fourier methods and refined by full-matrix least squares to R = 0.01 8 and 0.063 for ( 1) and ( 7) respectively. Neutral [PdCl,(dpk-H,0)] and cationic [AuCI2(dpk*H2O)]+ are present in the crystals of ( 1) and ( 7) respectively; the co-ordination geometry of the metal atom is square planar in both cases and involves two CI and two N atoms, thedpk*H,O molecule acting as a chelating N-donor ligand. The ligand conformation is very similar in both complexes, the six-membered chelate being in a boat form with a dihedral angle between the pyridyl rings of 114.54 and 11 6.63" respectively; this allows a very favourable co-ordination angle of 87.1 (2) and 86.4(6)", and a short contact between the oxygen atom of a hydroxyl group and the metal cation of 2.824(6) and 2.77(1) A for (1) and ( 7) respectively.A MOLECULE of di-2-pyridyl ketone (dpk) can, in princi-This was filtered off, washed ple, act as a bidentate nitrogen donor capable of formingThe yield was ca. 90%