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Diazide diamino complexes of Pt(iv) are considered as prospective prodrugs in oxygen-free photodynamic therapy (PDT). Primary photophysical and photochemical processes for cis,trans,cis-[Pt(N3)2(OH)2(NH3)2] and trans,trans,trans-[Pt(N3)2(OH)2(NH3)2] complexes were studied by means of stationary photolysis, nanosecond laser flash photolysis and ultrafast kinetic spectroscopy. The process of photolysis is multistage. The first stage is the photosubstitution of an azide ligand to a water molecule. This process was shown to be a chain reaction involving redox stages. Pt(iv) and Pt(iii) intermediates responsible for the chain propagation were recorded using ultrafast kinetic spectroscopy and nanosecond laser flash photolysis. The mechanism of photosubstitution is proposed. [ABSTRACT FROM AUTHOR]

Coordination of P,N indolyl-phosphine ligands to AuI, AgIand CuImetal ions under weakly basic conditions results in easy deprotonation of the indolyl N–H function and effective formation of a family of homo- and heterobimetallic complexes MM′(PPh2C9H7N)2(M = M′ = Au (2), Ag (5); M = Au, M′ = Cu (3), Ag (4)). The latter (4) exists as an inseparable mixture of four different complexes, which are in equilibrium driven by slow dynamics. The reaction of silver(i) and copper(i) ions with PPh2(C9H8N) affords a rare tetranuclear Z-shaped cluster Ag2Cu2(PPh2C9H7N)4(6), which exhibits red luminescence in solid state (650 nm) and a weak dual emission in solution with the main component in the near-IR region (746 nm). [ABSTRACT FROM AUTHOR]

The novel heterobimetallic Au(i)–M(i) (M = Cu, Ag) alkynyl-diphosphine clusters were effectively prepared using a family of dialkynyl-based diphosphines, PPh2–C2–(C6H4)n–C2–PPh2(n= 0–2). These compounds consist of [AuxMy(C2C6H4R)2x]y−xclusters (x= (n+ 2)(n+ 3)/2; y= (n+ 1)(n+ 2)) “wrapped” in gold–diphosphine “belts” (M = Cu, n= 0, R = H (4); n= 1, R = H (6), OMe (8), NMe2(9). M = Ag, n= 0, 1, 2, R = H (5, 7, 10). The solid-state structures of 5and 6have been determined by X-ray crystallographic studies, other complexes were characterized by NMR spectroscopy and ESI-MS measurements. The luminescence behavior of these compounds has been studied both in the solid state and solution, and intense room-temperature emission in fluid medium with maximum quantum yield of 0.5 (6) was detected. Computational studies have been carried out and the theoretical results obtained are in good agreement with the experimental data. The calculations provided additional information on the structural and electronic properties of the aggregates under investigation and allowed for the rationalization of the difference in their photophysical behavior. [ABSTRACT FROM AUTHOR]