Photophysical properties of 5H-dibenzo(a,d)cyclohepten-5-one in different solutions

Direct Photocatalyzed Hydrogen Atom Transfer (HAT) for Aliphatic C-H Bonds Elaboration

Direct photocatalyzed hydrogen atom transfer (d-HAT) can be considered a method of choice for the elaboration of aliphatic C–H bonds. In this manifold, a photocatalyst (PC_HAT) exploits the energy of a photon to trigger the homolytic cleavage of such bonds in organic compounds. Selective C–H bond elaboration may be achieved by a judicious choice of the hydrogen abstractor (key parameters are the electronic character and the molecular structure), as well as reaction additives. Different are the classes of PCs_HAT available, including aromatic ketones, xanthene dyes (Eosin Y), polyoxometalates, uranyl salts, a metal-oxo porphyrin and a tris(amino)cyclopropenium radical dication. The processes (mainly C–C bond formation) are in most cases carried out under mild conditions with the help of visible light. The aim of this review is to offer a comprehensive survey of the synthetic applications of photocatalyzed d-HAT.

Stokes and anti-Stokes Raman scattering of 5H-dibenzo(a,d)cyclohepten-5-ol

The ultraviolet absorption and emissions as well as Stokes and anti-Stokes Raman scatterings of spectroscopically pure 5H-dibenzo(a,d)cycloheptene-5-ol were investigated by flash and laser-flash photolysis technique in solution at room temperature and at 77K. The whole spectrum, absorption, excitation, prompt and delayed fluorescence, T-T absorption spectra were recorded photographically and photoelectrically in the ultraviolet and visible region and phosphorescence spectrum, Stokes, anti-Stokes scatterings were recorded at 77K.