Dynamic Gold(I) Complexes of Hexa‐ tert ‐butyl‐octaphosphane

Mechanochemical preparation of strongly emissive monosubstituted triarylphosphane gold(i) compounds activated by hydrogen bonding driven aggregations

Gold(i) triarylphosphane compounds are a well-known class of coordination compounds displaying from mild to strong emissive properties. Mechanochemical approaches to the preparation, spectroscopic characterization, X-ray diffraction structural determination, and photophysical studies of green emissive neutral linear monophosphane or neutral pseudo-T-shaped or cationic bis-phosphane gold(i) compounds, are herein discussed. The mechanochemical approach to the preparation of gold(i) derivatives was particularly successful for ligands bearing the carboxylic group, while the preparation with esterified ligands yields better results with solvent-mediated methods. The introduction of carboxyl or ester substituents in one aryl group favors the ligand-centered emissions. The analysis of the origin of the emissions was elucidated on the basis of DFT calculations, addressing the emissive behavior to ligand-centered excited states, strongly affected by supramolecular reversible hydrogen bonding aggregation. The study indicates that the ligand with the carboxylic group is particularly suitable for the mechanochemical preparation of emissive gold(i) complexes for material science applications.

Coordination Chemistry of Hepta-tert-butylnonaphosphane

Hepta-tert-butylnonaphosphane {cyclo-(P4tBu3)}2PtBu was employed as a ligand in transition metal complexes of iron(0) (1), cobalt(–I) (2), copper(I) (3) and rhodium(I) (4), which are readily formed in moderate to good yields,...

Gold(I) Complexes of Tetra-tert-butylcyclotetraphosphane

The reaction of tetra-tert-butylcyclotetraphosphane cyclo-(PtBu)4 (L) with one to four equivalents [AuCl(tht)] (tht = tetrahydrothiophene) leads to the gold(I) complexes [(AuCl)nL] (n = 1–4, 1–4) in which the ligand coordinates...

Facile synthesis of cyclo-(P4tBu3)-containing oligo- and pnictaphosphanes

The cyclo-(P₄^tBu₃) synthon [Li{cyclo-(P₄^tBu₃)}(thf)(tmeda)] (1) (thf = tetrahydrofuran, tmeda = N,N,N',N'-tetramethylethane-1,2-diamine) is readily accessible in a one-pot synthesis from P₄ and Li^tBu. The use of 1 as a cyclo-(P₄^tBu₃) building block enables the rational synthesis of cyclo-(P₄^tBu₃)-containing oligophosphanes, namely {cyclo-(P₄^tBu₃)}₂ (2), {cyclo-(P₄^tBu₃)}₂P^tBu (3) and {cyclo-(P₄^tBu₃)}₂CH₂ (4), C_3v-symmetric pnictaphosphanes E{cyclo-(P₄^tBu₃)}₃ (E = Bi, Sb, As; 5-7) as well as AsCl{cyclo-(P₄^tBu₃)}₂ (8). Compounds 5 and 6 represent the first neutral homoleptic bismuthane and stibane that contain only bonds to phosphorus. All new compounds were isolated in moderate to good yields and fully characterised. The ³¹P{¹H} NMR spectral data of 1, 2, 4, and 8 have been determined by automated line-shape analysis.

Selective formation of a supramolecular coordination complex in the nanometre scale with a ferrocene-based phospholane ligand

A straightforward synthesis of the tetradentate phospholane ligand 1 is reported. The 2 : 1 [M : L] reaction of 1 with [AuCl(tht)] (tht = tetrahydrothiophene) resulted in the 4 : 2 [M : L] supramolecular coordination complex 2 where two ligands 1 are bridging four gold(I) cations. The formation of 2 can be rationalised via a geometrical analysis of the ligand. The coordination mode of the gold atoms was evaluated based on a CSD search, revealing the geometrical changes for a transition from linear to trigonal planar coordination environment.

Versatile Coordination Chemistry of Hexa-tert-butyl-octaphosphine

The octaphosphine {cyclo-(P₄^tBu₃)}₂ (1) possesses a multifaceted coordination chemistry. The predominant binding mode is a P,P-chelate, e.g., in the monometallic chelate complex [MLL'(1-κ²P²,P^4')] in which the ligand 1 adopts a gauche conformation. Examples include square-planar (M = Rh^I, L = CO, L' = Cl (2), M = Pd^II, L = L' = Cl (3), M = Pt^II, L = L' = Cl (9)), tetrahedral (M = Co^-I, L = NO, L' = CO (4)), and trigonal-planar complexes [ML(1-κ²P²,P^4')] (M = Pd⁰, L = PPh₃, (5), M = Cu^I, L = Br (6)). With 2 equiv of [CuBr(SMe₂)], a dinuclear complex [(CuBr)₂(1-κ²P²,P^2',κ²P⁴,P^4')] (7) was obtained which features a synperiplanar conformation of the octaphosphine. A second coordination mode was also observed in [PtCl₂(1-κ²P¹,P^2')] (10) in which the bridge phosphorus atom in octaphosphine 1 is involved in the chelation, with the ligand in an antiperiplanar conformation. Thermolysis of selected complexes showed them to be suitable candidates for the generation of phosphorus-rich metal phosphides MP_x (x > 1).