The ability of the doublet excited state of perylene diimide anion radical 2(PDI–•)* to reduce aromatic electron acceptors was probed by picosecond time-resolved transient absorption (TA) spectroscopy. Excitation of PDI–• produces visible TA due to 2(PDI–•)* that decays with τ = 160 ps. Aromatic electron acceptors with varying reduction potential quench 2(PDI–•)* and, in some cases, give a new visible region absorption that is attributed to the products of bimolecular photoinduced electron transfer, 2(PDI–•)* + Ar–X → PDI + Ar–X–•. Stern–Volmer quenching of 2(PDI–•)* accomplished with a series of acceptors provides bimolecular quenching rate constants as a function of acceptor reduction potential. Rehm–Weller analysis of the electron transfer quenching data affords the potential for the (*PDI–•/PDI) electrochemical half-reaction as −1.87 V vs SCE.

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A side-chain-extended conjugation strategy is demonstrated here to improve photocatalytic performance of a linear conjugated polymer for hydrogen production from water. For it, polymer P0, P1, and P2 were designed...

Two classes of novel tetra-iron substituted sandwich-type arsenotungastates (ATs) with supporting lanthanide (Ln) pendants KNa2 [Ln(H2O)7][Fe4(H2O)10(B-β-AsW9O33)2]·21H2O [Ln = La(III) (1), Pr(III) (2), Nd(III) ()3, Sm(III) (4)] and [Ln(H2O)8]2[Fe4(H2O)8(l-thr)2(B-β-AsW9O33)2]·20H2O [Ln = La(III) (5), Pr(III) ()6, Nd(III) (7), Sm(III) (8), Eu(III) (9), Gd(III) (10), Tb(III) (11), Dy(III) (12), Er(III) (13)] (l-thr = l-threonine) have been synthesized by the hydrothermal reaction of the [As2W19O67(H2O)](14-) precursor with Fe(3+) cations and Ln(3+) cations in the presence of l-thr or l-leucine and l-alanine, and further characterized by elemental analyses, IR spectra and single-crystal X-ray diffraction. Structural analyses indicate that 1-4 display the inorganic 2-D sheet architecture constructed from tetra-iron sandwiched AT [Fe4(H2O)10(B-β-AsW9O33)2](6-) fragments by bridging [Ln(H2O)7](3+) cations whereas the molecular structures of the isostructural 5-13 consist of an organic-inorganic hybrid tetra-iron substituted sandwich-type AT [Fe4(H2O)8(l-thr)2(B-β-AsW9O33)2](6-) fragment and two pendant [Ln(H2O)8](3+) cations. As far as we know, 1-4 represent the rare inorganic 2-D extended ATs based on transition-metal substituted sandwich-type polyoxometalate units and Ln linkers and 5-13 are the first Fe-Ln heterometallic ATs with amino acid ligands. The solid state photoluminescence (PL) measurements of 9 and 11 have been performed at room temperature. The PL emission of 9 is mainly derived from the characteristic (5)D0 → (7)F2 (J = 4-0) transitions of the Eu(III) cations whereas the PL behavior of 11 stems from the common contribution of the (5)D4 → (7)FJ (J = 5-3) transitions of the Tb(III) ions and oxygen-to-metal (O → W) charge-transfer transitions of AT segments. The thermogravimetric (TG) analyses of 1-4 and 6-12 have been investigated.

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A facile synthesis of copper nanoparticles supported on an ordered mesoporous polymer was developed for solvent-free Sonogashira coupling reactions.

A sequential cross‐coupling/annulation of ortho‐vinyl bromobenzenes with aromatic bromides was realized, providing a direct and modular approach to access polycyclic aromatic compounds. A vinyl‐coordinated palladacycle was proposed as the key intermediate for this sequential process. Excellent chemoselectivity and regioselectivity were observed in this transformation. The practicability of this method is highlighted by its broad substrate scope, excellent functional group tolerance, and rich transformations associated with the obtained products.

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