No abstract

Synthetically useful radical thiol-ene reactions can be initiated by visible-light irradiation in the presence of an organic photocatalyst, 9-mesityl-10-methylacridinum tetrafluoroborate. The key thiyl radical intermediates are generated upon quenching of the photoexcited catalyst with a variety of thiols. The success of this method requires only the use of near-stoichiometric levels of alkene coupling partners. Using these highly efficient metal-free conditions, thiol-ene reactions between carbohydrates and peptides can be accomplished in excellent yields.

A set of new ferrocene-diketopyrrolopyrrole (Fc-DPP) conjugated dyads was synthesized and their optical, nonlinear optical (NLO) and electrochemical properties were investigated. The second-order nonlinear polarizabilities were determined using Hyper-Rayleigh Scattering with femtosecond pulsed laser light at 840 nm. The dyads depicted structure dependent NLO response, which could be explained by correlating optical as well as electrochemical data. In the latter case, it is shown that the amplitude of the Fc based one-electron redox process of D-π-A type dyads is doubled in the dyads of the type D-π-A-π-D, where the acceptor (DPP) is flanked by two Fc donors. Please do not adjust marginsPlease do not adjust margins diisopropyl succinate (8.10 g, 40 mmol) over a period of 1 h. Reaction mixture was heated at 85 °C for 2 h, after which it was cooled to 50 °C and 50 ml methanol was added. The reaction mixture was neutralized using glacial acetic acid and stirred for 15 min. and then cooled to ambient temperature and the contents were filtered over sintered glass (G4) funnel. Residue was washed twice with hot methanol and de-ionized water to yield analytically pure dark red solid 1 (61%). Mp> 300 o C IR (KBr): ν max 1628, 1648, 3153 and 3417 cm -1 .

We report a metal-free photocatalytic approach to the synthesis of glycoconjugates, highlighting the mild nature of the reaction conditions.

New, thermally stable dipolar ferrocene–diketopyrrolopyrrole (Fc–DPP) dyads with alkene as a linker exhibited structure dependent first hyperpolarizabilities,βHRS, recorded by a femtosecond HRS technique using a femtosecond (120 fs) pulsed laser light system at 900 nm at ambient temperature.

No abstract

Thermally stable ferrocene-α-cyanostilbenes exhibit non-zero dipole moments as well as good structure dependent second order nonlinear optical response.

The development of a visible-light-mediated oxidative cleavage of electron-deficient indoles is reported. Methylene blue serves as an effective catalyst and the transformation shows a broad substrate scope. A variety of functional groups are well accommodated in the mild reaction conditions. The photo-mediated single electron transfer and oxidative cleavage mechanisms were investigated via density functional theory and Marcus theory calculations.