Simple metal-free organic D-pi-A dyes with alkoxy- or fluorine substitutions: application in dye sensitized solar cells.

Two new metal-free organic sensitizers with simplest structural variations have been synthesized for application in nanocrystalline TiO2 sensitized solar cells. The donor-pi-bridge-acceptor (D-pi-A) structure dyes, Y2 and Y3 each designed with three parts, an electron donor unit (substituted phenyl), a linker unit (thiophene), and an anchor unit (cyanoacrylic acid) showed maximal monochromatic incident photon to current conversion efficiencies (IPCE) in a device reaching upto 67% and 82% respectively. The organic sensitizers with 3,4,5-trimethoxy phenyl (Y3) as donor moieties obtained better solar light to electrical energy conversion efficiencies of 3.

Iron-catalyzed regioselective direct oxidative aryl-aryl cross-coupling.

Regioselective iron-catalyzed cross-dehydrogenative coupling (CDC) of two aromatic compounds using tert-BuOOH as oxidant under mild conditions has been reported. The direct oxidative coupling reaction is selective toward creation of a carbon-carbon bond at the position ortho to the functional groups of the substrates, completely preventing the homocoupled products. The C-C bond-forming reaction makes the method versatile, leading to functionalized 2,2' -disubstituted biaryls.