Although reversible covalent activation of molecular hydrogen (H2) is a common reaction at transition metal centers, it has proven elusive in compounds of the lighter elements. We report that the compound (C6H2Me3)2PH(C6F4)BH(C6F5)2 (Me, methyl), which we derived through an unusual reaction involving dimesitylphosphine substitution at a para carbon of tris(pentafluorophenyl) borane, cleanly loses H2 at temperatures above 100 degrees C. Preliminary kinetic studies reveal this process to be first order. Remarkably, the dehydrogenated product (C6H2Me3)2P(C6F4)B(C6F5)2 is stable and reacts with 1 atmosphere of H2 at 25 degrees C to reform the starting complex. Deuteration studies were also carried out to probe the mechanism.

Organic photovoltaic devices that can be fabricated by simple processing techniques are under intense investigation in academic and industrial laboratories because of their potential to enable mass production of flexible and cost-effective devices. Most of the attention has been focused on solution-processed polymer bulk-heterojunction (BHJ) solar cells. A combination of polymer design, morphology control, structural insight and device engineering has led to power conversion efficiencies (PCEs) reaching the 6-8% range for conjugated polymer/fullerene blends. Solution-processed small-molecule BHJ (SM BHJ) solar cells have received less attention, and their efficiencies have remained below those of their polymeric counterparts. Here, we report efficient solution-processed SM BHJ solar cells based on a new molecular donor, DTS(PTTh(2))(2). A record PCE of 6.7% under AM 1.5 G irradiation (100 mW cm(-2)) is achieved for small-molecule BHJ devices from DTS(PTTh(2))(2):PC(70)BM (donor to acceptor ratio of 7:3). This high efficiency was obtained by using remarkably small percentages of solvent additive (0.25% v/v of 1,8-diiodooctane, DIO) during the film-forming process, which leads to reduced domain sizes in the BHJ layer. These results provide important progress for solution-processed organic photovoltaics and demonstrate that solar cells fabricated from small donor molecules can compete with their polymeric counterparts.

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All or nothing: Sterically frustrated Lewis pairs of phosphines and the borane B(C6F5)3 exhibit unprecedented reactivity with olefins to afford both inter‐ and intramolecular alkanediyl‐linked phosphonium borates (see picture; black C, pink F, green B, orange P). These reactions are all the more remarkable given that any pair of these reagents do not react while the combination of all three reagents results in product formation.

In their Communication the authors stated that "non-transition-metal catalysts for hydrogenation reactions are all but unknown." However, it should be noted that non-transition-metal systems have been shown to effect hydrogenation under more forcing conditions. For example, DeWitt, Ramp, and Trapasso demonstrated hydrogenation with iPr 3 B under 67 atm (1000 psi) H 2 at 220 o C. [1] Similarly, Haenel and co-workers [2] among others [3] showed hydrogenation of coal under almost 148 atm (15 MPa) H 2 and at 280-350 8C using BI 3 or alkyl boranes. As well, superacid systems have also been shown to effect hydrogenation of alkenes at H 2 pressures of at least 35 atm. [4] [1] a) E.