Intermolecular photoreductions of ketones

Synthesis of ruthenium particles by photoreduction in polymer solutions

“…Scaiano et al [14] have recently reported that silver nanoparticles are synthesized using ketyl radicals generated by the photoirradiation of benzophenone. They found that ketyl radicals, produced in the photoreduction of ketone analogues [15], are excellent reducing agents and efficiently convert Ag + to Ag 0 in surfactant micelles. We recently demonstrated that the photochemical reduction of platinum (Pt(IV)) and gold (Au(III)) under the existence of PVP in water and ethanol mixture could produce a colloidal dispersions of Pt and Au particles [16].…”

Laser-induced photochemical gas-phase reactions of vibrationally excited triplet molecules

“…Under PBG less than 10 Torr and initial temperature T= 433K the two components ofthe DF with collisionless decay time of 10 In the presence of hydrogen donor the spectra, intensities I and decay rates K of the DF changed with Pbg in the following manner. 1 . As is seen from Fig.…”

“…In such a case photochemical production of ketyl radica' after photoexcitation in the presence of hydrogen donors has the high reaction rate For example for benzophenone, reaction of direct hydrogen abstraction was suggested to consider as follows BP+H-R hv > 3BP*+H_R .BP-H+.R (1).…”

“…During last years the mechanisms of photoreduction for many carbonyl compounds was an active area of research [1][2][3][4] 2. Adding BG leads to a decrease in the time integrated relative intensity of the fast component I, described by the Stern-Volmer relation: la/I l+tPbgZ where I and 1 are the time-integrated intensities ofDF ofthe vapours and their mixtures with BG; 3 is the efficiency of vibrational energy transfer; Z is the rate constant of gas kinetic collisions; z is the lifetime of the vibrationally excited triplet molecules.…”

Aluminum Phthalocyanine on Silica Nanoparticles: Aggregation and Excited States

“…This value is typical for the rate constants of quenching of triplet states of organic molecules by molecular oxygen (usually (2-5)·10 9 M -1 ·s -1 ) via energy transfer to form singlet oxygen. [23][24][25] It is known that the quantum yield of 1 О 2 upon photolysis of Pc can be in the range of 0.1-0.7. [5,6] In deoxygenated solutions, the kinetics of decay of T m is described by the first-order rate constant of 7.8·10 3 s -1…”