Diphenylsilane-Palladium -Zinc

Diisobutylaluminum hydride-Boron trifluoride etherate, 116 Diphenylsilane-Palladium(II) chlo-ride-Triphenylphosphine, 126 Diphenylsilane-Tetrakis(triphenyl-phosphine)palladium(0)-Zinc chloride, 126... 

Palladium-Catalyzed Conjugate Reduction of a,s-Unsaturated Carbonyl Compounds with Diphenylsilane and Zinc Chloride Cocatalyst a,B-Dihydro-B-Ionone... 

Diphenylsilane-Tetrakis(triphenyl-phosphine)palladium(0)-Zinc chloride, 126... 

Enones can be reduced to the saturated ketones with triethylsilane and Wilkinson s catalysis62 (equation 54). Interestingly, the same product was prepared via a Tiffeneau-Demjanov ring expansion wherein trimethylsilyl cyanide was used (equation 55). The selective reduction of the double bond of enones can also be carried out with diphenylsilane in the presence of palladium(O) or palladium(II) and zinc chloride63 (equation 56), or more effectively with phenylsilane and molybdenum hexacarbonyl64 (equation 57). This latter reagent was also used to reduce the double bond of a,/ -unsaturated esters, amides and nitriles. 

Attempts to convert the sulfones back into PASHs have been successful with a number of agents such as various metals (zinc, tin, magnesium, aluminum, iron, and nickel) in acetic acid, palladium on carbon with hydrazine, stannous chloride, lithium triethylborohydride, diphenylsi-lane, sodium borohydride, boron trifluoride, dicyclohexylcarbodiimide, triethyl phosphite, dimethyl dichlorosUane with lithium aluminum hydride, diphenylsilane, and triphenyl phosphine with iodine. However, none of them cleanly effect this conversion. 

Related Reagents. Diphenylsilane-Tetrakis(triphenylphos-phine)palladium(0)-Zinc Chloride. 

Related Reagents. Aluminum Chloride Diphenylsilane-Tetrakis(triphenylphosphine)palladium(0)-Zinc Chloride Phos-phorus(in) Chloride-Zinc(II) Chloride Phosphorus Oxychlo-ride-Zinc(II) Chloride Tin(rV) Chloride Tin(IV) Chloride-Zinc Chloride Titanium(IV) Chloride Zinc Bromide. 

---