Efficient Method for Thioacetalization of Carbonyl Compounds in the Presence of a Catalytic Amount of Benzyltriphenylphosphonium Tribromide (BTPTB) under Solvent-Free Conditions

A variety of carbonyl compounds have been successfully converted to the corresponding thioacetal derivatives in good to excellent yields on reaction of carbonyl compounds with 1,2-ethanedithiole, 1,3-propanedithiol, and ethylthiol in the presence of a catalytic amount of benzyltriphenylphosphonium tribromide (BTPTB) under solvent-free conditions. Some of the major advantages of this method are mild reaction conditions, high efficiency, and the compatibility with other reported methods. In addition, no bromination occurs at the double bond or α to the keto position or even in the aromatic ring under these experimental conditions.     

Synthesis of Methyltriphenylphosphonium Peroxydisulfate as a Mild Selective Reagent for the Oxidation of Alcohols

Methyltriphenylphosphonium peroxydisulfate (MTPPP) was synthesized by treating methyltriphenyl bromide and potassium peroxydisulfate in aqueous solution. This was used as an efficient and selective reagent for oxidation of alcohols to their corresponding carbonyl compounds in good to high yields.     

Application of dimeric cyclopalladated complex of tribenzylamine as an efficient catalyst in the Heck cross-coupling reaction

The activity of [Pd{C₆H₄(CH₂N(CH₂Ph)₂)} (μ-Br)]₂ complex was investigated in the Heck-Mizoroki C-C cross-coupling reaction. This complex is an active and efficient catalyst for the Heck reaction of aryl iodides, bromides and even chlorides and also arenesulfonyl chlorides. The cross-coupled products were produced in excellent yields in short reaction time using a catalytic amount of [Pd{C₆H₄(CH₂N(CH₂Ph)₂) (μ-Br)]₂ complex in NMP at 130 °C.