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The coordination of the ligands with respect to the central atom in the complex bromidotricarbonyl[diphenyl(pyridin-2-yl)phosphane-κ2 N,P]rhenium(I) chloroform disolvate, [ReBr(C17H14NP)(CO)3]·2CHCl3 or [κ2-P,N-{(C6H5)2(C5H5N)P}Re(CO)3Br]·2CHCl3, (I·2CHCl3), is best described as a distorted octahedron with three carbonyls in a facial conformation, a bromide atom, and a biting P,N-diphenylpyridylphosphine ligand. Hirshfeld surface analysis shows that C—Cl...H interactions contribute 26%, the distance of these interactions are between 2.895 and 3.213 Å. The reaction between I and piperidine (C5H11N) at 313 K in dichloromethane leads to the partial decoordination of the pyridylphosphine ligand, whose pyridyl group is replaced by a piperidine molecule, and the complex bromidotricarbonyl[diphenyl(pyridin-2-yl)phosphane-κP](piperidine-κN)rhenium(I), [ReBr(C5H11N)(C17H14NP)(CO)3] or [P-{(C6H5)2(C5H5N)P}(C5H11N)Re(CO)3Br] (II). The molecule has an intramolecular N—H...N hydrogen bond between the non-coordinated pyridyl nitrogen atom and the amine hydrogen atom from piperidine with D...A = 2.992 (9) Å. Thermogravimetry shows that I·2CHCl3 losses 28% of its mass in a narrow range between 318 and 333 K, which is completely consistent with two solvating chloroform molecules very weakly bonded to I. The remaining I is stable at least to 573 K. In contrast, II seems to lose solvent and piperidine (12% of mass) between 427 and 463 K, while the additional 33% loss from this last temperature to 573 K corresponds to the release of 2-pyridylphosphine. The contribution to the scattering from highly disordered solvent molecules in II was removed with the SQUEEZE routine [Spek (2015). Acta Cryst. C71, 9-18] in PLATON. The stated crystal data for M r, μ etc. do not take this solvent into account.

The reaction of [Re I Br(CO)3(THF)]2 with phenanthroline in solution leads to the diimine rhenium(I)tricarbonyl [(phen)Re(CO)3Br] and the dimer [(CO)3(phen)Re(µ-OH)(phen)Re(CO)3] + Br-(1 + Bras as a by-product (∼ 5% yield). This latter bimetallic compound crystallizes as a mixture of three polymorphs, with variable amount of solvent: 1 + Br-•CHCl3 (triclinic and orthorhombic) and 1 + Br-•2(CHCl3) (triclinic). Rietveld analysis showed 38, 54 and 8% of 1 + Br-•CHCl3 (triclinic), 1 + Br-•CHCl3 (orthorhombic) and 1 + Br-•2(CHCl3) (triclinic) respectively. The 1 + cation shows two [Re I (phen)(CO)3] + units connected by means of a central hydroxyl group. Noteworthy, the bridging Re−O−Re angle varies between 130.9(7)° to 140.7(2)° along the polymorphic series. UV-vis spectrum for the 1 + shows a broad absorption band around 390 nm in CH2Cl2 which has been attributed to has MLCT character (Re(dπ)→π*(phen)) as confirmed by DFT. Excitation at 405 nm in solution leads to emission at 595 nm (DCM), 605 nm (DMF) and 625 nm (CH3CN). The emission follows a mono-exponential law of decay and has lifetime of 405.8 ns (DCM). The solid-state polymorphic mixture absorbs around 460 nm. Excitation of the solid at 320 nm leads to emission with a maximum at 575 nm, which follow a bi-exponential law of decay with two components, a short one τ1 of 27.0 ns and longer one τ2 of 178.5 ns. These results suggest that the emitting state does not vary as function of the molecular geometry.

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8-(dimethylamino)-N,N-dimethyl-naphthalen-1-aminium hydrogenterephthalate (PSH + TPAH -) and 8-(dimethylamino)-N,N-dimethylnaphthalen-1aminium hydrogen-terephthalate hydrate (PSH + TPAH -•H2O) were prepared by the direct reaction of N 1 ,N 1 ,N 8 ,N 8 -tetra-methyl-naphthalene-1,8-di-amine, Proton Sponge (PS) © and terephthalic acid (TPAH2) in a 1:1 stoichiometric relation. The structure of both salts is constructed on the base of 1D chains defined by hydrogen bonding of the anionic carboxylate end and the carboxylic acid of TPAHanion. Additionally for the structure of PSH + TPAH -•H2O the water molecules connect this 1D chains through hydrogen bonds, then defining a 1D-belt. In both cases the PSH + provides balance of charge among the chains.