Shear- and UV-induced fluorescence switching in stilbenic pi-dimer crystals powered by reversible [2 + 2] cycloaddition.

We have designed and synthesized asymmetric cyano-stilbene derivatives containing trifluoromethyl (-CF(3)) substituents with the aim of producing tightly packed pi-dimer systems that as crystals exhibit reversible [2 + 2] cycloaddition with characteristic fluorescence modulation. (Z)-3-(3',5'-Bis(trifluoromethyl)biphenyl-4-yl)-2-(4'-(trifluoromethyl)biphenyl-4-yl)acrylonitrile (CN(L)-TrFMBE) and its derivatives were found to form antiparallel pi-dimer stacks in crystals due to their specific intermolecular interactions, including C-F..

Comment on 'aggregation-induced phosphorescent emission (AIPE) of iridium(III) complexes': origin of the enhanced phosphorescence.

An investigation of the photophysics of Ir(III) complexes with controlled ligand structures and our quantum chemical calculations attest that the most probable explanation for the reported 'aggregation-induced phosphorescent emission', which was originally claimed to be related to an intermolecular excimer, is restricted intramolecular motion.

{μ-N,N'-Bis[(E)-4-pyridylmethyl-idene]naphthalene-1,5-diamine}bis-[dichlorido(dimethyl sulfide)platinum(II)].

The title dinuclear platinum compound, [Pt(2)Cl(4)(C(22)H(16)N(4))(C(2)H(6)S)(2)], with a long bridging bipyridyl-type ligand, is centrosymmetric and the Pt(II) cation shows a slightly distorted square-planar coordination geometry. The Cl ligands are trans to each other, with a Cl-Pt-Cl angle of 178.83 (8)°.

Dinuclear palladium-azido complexes containing thiophene derivatives: reactivity toward organic isocyanides and isothiocyanates.

Cyclopalladated tetranuclear Pd(II) complexes, [Pd2(micro-Cl)2(Y)]2 (Y = L1 or L2; H2L1 = di(2-pyridyl)-2,2'-bithiophene; H2L2 = 5,5''-di(2-pyridyl)-2,2':5',2''-terthiophene), containing two pyridyl-alpha, alpha'-disubstituted derivatives of thiophene were prepared. Treating these products with PR3 and subsequently with NaN3 produced the dinuclear Pd-azido complexes [(PR3)2(N3)Pd-Y-Pd(N3)(PR3)2] (Y = L1 or L2) or a cyclometallated complex [(PR3)(N3)Pd-Y'-Pd(N3)(PR3)] (Y' = C,N-L2). Reactions of these Pd-azido complexes with CN-Ar (Ar = 2,6-Me(2)C(6)H(3), 2,6-i-Pr(2)C(6)H(3)) or R-NCS (R = i-Pr, Et, allyl) led to the complexes containing end-on carbodiimido groups [(PMe3)2(N[double bond]C[double bond]N-Ar)Pd-Y-Pd(N[double bond]C[double bond]N-Ar)(PMe3)2] or S-coordinated tetrazole-thiolato groups {(PMe3)2[CN4(R)]S-Pd-Y-Pd-S[CN4)(R)](PMe3)2}.