Synthesis on the basis of electrogenerated carbenes

A series ofS _N2 reactions with halomethanes as substrates and the corresponding anions as nucleophiles were studied by the semiempirical MNDO and AM1 methods, taking into account solvent effects. Analysis of the kinetics, structures of reagents, intermediates and products, and charge distribution in them allows one to draw the conclusion that the retardation ofS _N2 reactions is stronger in solvents than in the gas phase, and the rates of reactions involving anions with a lower number of halogen atoms are higher.For Part 8 see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2148–2154, November, 1995.This work was partially financially supported by the International Science Foundation (Grant No. MHYOO).     

Preparation of polyalkylviologen–polyanion complexes and their applications to the debromination of diphenyl bromomethane under heterophase condition

Several polyelectrolyte complexes were prepared by the reaction of polyalkylviologens [polyethylviologen (PEV²⁺), polypropylviologen (PPrV²⁺), and polybutylviologen (PBV²⁺)] with polyanions [sodium alginic (ALG), sodium polyacrylate (PAA), or sodium polystyrenesulfonate (PSS)]. These complexes were used as electron-transfer catalysts (ETC) on the debromination of diphenyl bromomethane (Ph₂CHBr) under heterophase condition [reductant: Na₂S₂O₄, in H₂O (liquid)-polyelectrolyte complex(S)—Ph₂CHBr in CH₂Cl₂]. The work showed that these complexes could induce the debromination of Ph₂CHBr to afford tetraphenyl ethane, and different polyanions in the complexes also affected the mediating abilities. © 1994 John Wiley & Sons, Inc.     

SO4^2—／TiO2固体酸催化剂的酸强度及光催化性能

SO4^2-/TiO2固体酸可用于光催化降解溴代甲烷,其光催化性能明显优于TiO2光催化剂,晨相同反应条件下,SO4^2-/TiO2的光催化活性比TiO2提高2－10倍,当H2S4浸渍液浓度为1mol/L时,制得的SO4^2-/TiO2酸性最强（H0＜－12.14）,具有超强酸性和最高的光催化活性。