CoCl2 System Research Articles

Ball milling as an effective method to prepare magnetically recoverable heterometallic catalysts for alcohol oxidation

Heterometallic double Fe2O3–CoCl2, CoCl2–V2O5, MoO3–V2O5, and triple CuO–Fe2O3–CoCl2 3d metal dispersed systems were easily prepared by ball milling at room temperature and characterized by scanning electron microscopy (SEM), field emission gun scanning electron microscopy (FEGSEM), energy-dispersive X-ray spectroscopy (EDX) and transmission electron microscopy (TEM). They catalyze the microwave-assisted solvent-free heterogeneous oxidation of 1-phenylethanol to acetophenone with tert-butyl hydroperoxide (t-BuOOH) as oxidant, used as a model reaction. In most of the heterometallic systems a significant improvement in the catalytic activity was observed in comparison to homometallic ones. For the tested catalytic systems and experimental conditions, the CuO–Fe2O3–CoCl2 and Fe2O3–CoCl2 systems exhibit the highest activity with maximum 78% yield and TON 39 after 1h. The possibility of magnetic recovery of the catalysts was demonstrated for the Fe2O3–CoCl2 (3:1) system.

ChemInform Abstract: Cleavage of Se-Se Bond by Sm/cat. CoCl2 System: A Novel Method for the Synthesis of Selenoesters.

Abstract The Sm/cat. CoCl2 system promoted diselenides to react with anhydrides or acyl chlorides to afford selenoesters in good yield under mild and neutral conditions.

A Novel Synthesis of Unsymmetrical Selenides via the Cleavage of Se–se Bond by Sm/cat.CoCl2 System

Promoted by Sm/cat. CoCl2 system, the Se–Se bond of diaryldiselenides was easily cleaved to form a “living” intermediate, which reacted readily with alkyl halides to afford unsymmetrical alkylarylselenides in good yields under mild and neutral reaction conditions.

Cleavage of Se-Se bond by Sm/cat.CoCl2 system a facile and novel method for the preparation of selenoesters

The Sm/cat.CoCl 2 system promoted diselenides to react with anhydrides or acyl chlorides to afford selenoesters in good yields under mild and neutral conditions.

Cleavage of Se-Se Bond by Sm/cat. CoCl2 System: A Novel Method for the Synthesis of Selenoesters

The Sm/cat. CoCl2 system promoted diselenides to react with anhydrides or acyl chlorides to afford selenoesters in good yield under mild and neutral conditions.

Zur katalytischen Reduktion aromatischer Stickstoffverbindungen und Diazene in Gegenwart von �bergangsmetallverbindungen

The NaBH4 reduction of nitrosobenzene to hydrazobenzene/aniline≈3 : 1, phenylhydroxylamine to aniline, azoxybenzene to hydrazobenzene, azobenzene to hydrazobenzene, and hydrazobenzene to aniline is catalysed by bis(dimethylglyoximato)cobalt compounds (“cobaloximes”), CoCl2, and some other salts of transition metals. The NaBH4−CoCl2 system is a convenient and mild reducing agent which effects the reduction of e.g.trans-azobenzene to hydrazobenzene even at −60°C. The diazene configuration has no effect on the reduction of the N=N group;cis-fixed benzo[c]cinnoline is smoothly converted into 2.2′-diaminobiphenyl. Aliphatic diazeneslike 2.3-diazanorbornene andtrans-di-1-adamantyldiazene do not react.