A new protocol for the photoinduced addition reaction of sulfides with benzophenones has been extablished, affording the αfunctionalized products. The effects of UV wavelength, temperature, concentration of reactants, concentration of Lewis acid catalyst and other factors on the isolated product yield have been investigated. The optimum condition is: UV light wavelength of 313 nm, room temperature, 0.02 mmol of 4,4dimethoxybenzophenone, 0.002 mmol of the catalyst of AlCl3. Under optimum conditions, the isolated yield of the desired product (4methoxyphenyl) (2tetrahydrothienyl) methanol is 57%. Based on the experiment results and corresponding literature reports in this field, a possible mechanism is discussed.

he RMG380 marine fuel oil was prepared by vacuum residue, coking wax oil and ethylene tar, the oil-soluble viscosity depressant was synthesized by maleic anhydride, styrene and octadecyl acrylate(MSA). The optimized synthesis conditions are as follows: octadecyl acrylate, styrene and maleic anhydride monomer ratio 5∶1∶3, dosage of initiator 0.6%, synthetic temperature 90 ℃, reaction time 6 h. This synthesized viscosity depressant was evaluated under the concentration of 300 mg/L and shear rate of 2 000 r/min at 50 ℃, the ratio of viscosity reduction of marine fuel oil can reach 66.11%, and meet the ISO8217—2005 RMG380 viscosity requirements of marine fuel oil. Meanwhile, this viscosity depressant was suitable for different marine fuel oil, while viscosity reducing effect gradually weakened with the increase of time.