Substitution reactivity and structural variability induced by tryptamine on the biomimetic rhenium tricarbonyl complex.

A series of seven -[Re(CO)(5Me-Sal-Trypt)(L)] complexes containing tryptamine on the , 5-methyl-salicylidene bidentate ligand backbone and where L is MeOH, Py, Imi, DMAP, PPh coordinated to the 6th position have been studied, including the formation of a dinuclear Re cluster. The crystallographic solid state structures show marked similarity in structural tendency, in particular the rigidity of the Re core and the hydrogen bond interactions similar to those found in protein structures. The rates of formation and stability of the complexes were evaluated by rapid time-resolved stopped-flow techniques and the methanol substitution reaction indicates the significant activation induced by the use of the , salicylidene bidentate ligand as manifested by the second-order rate constants for the entering nucleophiles.

2,6-Dichloro-aniline-4-(2,6-dichloro-anilino)-pent-3-en-2-one (1/2).

The asymmetric unit of the title compound, C6H5Cl2N·2C11H11Cl2NO, is composed of one mol-ecule of an enamino-ketone [i.e. -(2,6-dichloro-phenyl-amino)-pent-3-en-2-one] and half a mol-ecule of 2,6-dichloro-aniline, the whole mol-ecule of the latter component being generated by twofold rotational symmetry.

4-(2-Chloro-phenyl-amino)-pent-3-en-2-one.

In the title compound, C(11)H(12)ClNO, intra-molecular N-H⋯O hydrogen bonding is present. The dihedral angle between the benzene ring and the pentenone unit is 46.52 (5)°.

4-(2,3-Dimethyl-anilino)pent-3-en-2-one.

In the title compound, C(13)H(17)NO, the dihedral angle between the aryl ring and the amino-acryl-aldehyde mean plane [N-C=C-C=O; maximum deviation = 0.0144 (9) Å] is 53.43 (4)°.

Dicarbon-yl[4-(2,6-dimethyl-phenyl-amino)-pent-3-en-2-onato-κ(2)N,O]rhodium(I).

In the title compound, [Rh(C(13)H(16)NO)(CO)(2)], a square-planar coordination geometry is observed around the Rh(I) atom, formed by the N and O atoms of the bidentate ligand and two C atoms from two carbonyl ligands. The Rh(I) atom is displaced from the plane through these surrounding atoms by 0.0085 (2) Å.

4-(2,6-Dibromo-4-fluoro-anilino)pent-3-en-2-one.

The title enamino-ketone, C(11)H(10)Br(2)FNO, has a roughly planar pentenone chain; the maximum displacement of an atom from the pentenone plane is 0.071 (4) Å. The dihedral angle between the benzene ring and the pentenone unit is 77.

4-[(4-Methyl-phen-yl)amino]-pent-3-en-2-one.

The title enamino-ketone, C(12)H(15)NO, is a derivative of 4-(phenyl-amino)-pent-3-en-2-one with an approximately planar pentenone backbone, the greatest displacement from the plane being 0.042 (1) Å; the asymmetry in C-C distances in the group suggests the presence of unsaturated bonds. The dihedral angle between the benzene ring and the pentenone plane is 29.

4-(2-Methyl-anilino)pent-3-en-2-one.

The title enamino ketone, C(12)H(15)NO, a derivative of 4-(phenyl-amino)-pent-3-en-2-one, presents a roughly planar [greatest displacement of an atom from the pentenone plane is 0.033 (2) Å] pentenone backbone, enhanced by an intra-molecular N-H⋯O hydrogen bond; the asymmetry in C-C distances in the group suggests the presence of unsaturated bonds. The overall geometry in the free ligand differs significantly from that in other reported compounds, in which it is coordinated to rhodium; this is reflected in the bond distances [the N⋯O distance is significantly increased (0.

Isomorphism in monomeric 1:3 complexes of silver(I) salts with tri-p-tolylphosphine.

Reaction of silver(I) salts with three equivalents of tri-p-tolylphosphine in CH(3)CN resulted in a series of isomorphous complexes [AgX{P(4-MeC(6)H(4))(3)}(3)] (X = Br, SCN, ClO(4)). These complexes all crystallize in the orthorhombic space group Pna2(1). The complexes with X = Br, SCN are distorted tetrahedral around the silver(I) atom, whereas the ClO(4)(-) complex is distorted trigonal planar around the silver.

Polymorphism in iodotris(tri-p-tolylphosphine)silver(I).

The reaction of silver(I) iodide with tri(p-tolyl)phosphine in MeCN solution in 1:3 molar ratio yields a polymorph of the complex of the formula [AgI{P(4-MeC6H4)3}3], with the Ag atom in a distorted tetrahedral environment. A polymorphic structure of this complex (a) is compared with previously published crystal structures (b), determined at different temperatures. The two polymorphs are compared using r.

Carbonyl[4-(2,6-dimethyl-phenyl-amino)pent-3-en-2-onato-κN,O](triphenyl-phosphine-κP)rhodium(I) acetone hemi-solvate.

In the title compound, [Rh(C(13)H(16)NO)(C(18)H(15)P)(CO)]·0.5C(3)H(6)O, the Rh atom exhibits a square-planar coordination geometry, being coordinated by the N and O atoms of the bidentate β-diketonato ligand, a P atom from the triphenyl-phosphine unit and a C atom from the carbonyl group. The asymmetric unit also contains a disordered half-mol-ecule, lying about an inversion center, of the acetone solvate.

Carbon-yl[4-(2,3-dimethyl-phenyl-amino)pent-3-en-2-onato-κN,O](triphenyl-phosphine-κP)rhodium(I).

In the title compound, [Rh(C(13)H(16)NO)(C(18)H(15)P)(CO)], the coordination geometry of the Rh(I) atom is square-planar, formed by the coordinating N and O atoms of the bidentate enaminoketonate ligand, one C atom from the carbonyl group and a P atom from triphenyl-phosphine. The complex displays a 0.591 (3):0.