Sharif Digital Repository

Ruthenium complexes with their wide range of stable but chemically accessible oxidation states have been extensively studied as catalyst of hydrocarbon oxidation. In recent years, these complexes with various ligands have been reported as new catalysts with better selectivity and several co-oxidations. Ruthenium complexes act as oxidation catalyst, often via ruthenium-oxo species as active intermediates in the oxygen transfer process, oxidizing alcohols or alkanes and epoxidizing alkane. Here, we reported the synthesis and catalytic activity of a ruthenium(III) complex with bidentate oxazine ligand. The new synthesized Ru(III)-oxazine complex was characterized by IR and UV-Vis spectra and... 

Considerable efforts have been directed in recent years towards the transition metal complex catalyzed oxidation of organic compounds. Among these, oxidation of sulfides to sulfoxides and alkenes to epoxides have specially been attended a lot, since sulfoxides and epoxides are important intermediates in organic synthesis. In this study [MoO(O2)(oxazine)2] complex has been synthesized and characterized by FT-IR and 1HNMR. This complex was found to be an efficient, selective catalyst for the oxidation of various sulfides to sulfoxides with urea hydrogen peroxide (UHP) in excellent yields (100% for dioctylsulfide) and short reaction times (20 min) at room temperature. Also this new efficient... 

In this study new manganese(III) complexes of phox [Mn(phox)2(MeOH)2](ClO4), (phox= 2-(2` hydroxyphenyl)-5,6-dihydro-1,3-oxazine) have been synthesized and characterized with CHN,NMR and IR.The six-membered bidentate (N,O) oxazine ligand have been widely used throughout organometallic and inorganic chemistry, and are particularly important in homogeneous catalysis. The presence of N and O donor sites in oxazines may modify significantly the ligand roles for the variation of steric and electronic properties. Therefore, such systems are worth exploring for new catalytic uses . Catalytic oxidation reactions provide excellent alternatives for the use of stoichiometric reagents like urea... 

In this study, a catalyst-free Mannich reaction is applied for synthesis of 1,3-oxazines as an important class of biologically active compounds. In order to consider environmental application a mixture of water and ethanol is selected as a solvent for the reaction of 2,7-dihydroxynaphthalene with formaldehyde and an amine. Primary consideration of substitution effect on the reaction revealed that aniline and its derivatives with electron-donating substituent and halogens, cause higher yield. Aliphatic amines are not good substrate for this reaction with the exception of benzyl amine  

In nature, catalysis is of vital importance in a wide variety of biochemical processes catalyzed by metalloenzymes. The functions performed by the metalloenzymes and their significance have inspired a range of biomimetic studies, and intense efforts have been concentrated on the synthesis of low molecular weight complexes to model the spectroscopic features of such enzymes. Concomitantly, a challenging frontier in the field of biomimetic chemistry is the development of highly reactive model compounds that are able to effect rapid and selective substrate conversion. Some important catalytic transformations that have gained attention in recent years involve the carbon-carbon coupling, olefin... 

In this study a novel oxo-diperoxo tungsten(VI) complex [WO(O2)2(phox)] was prepared by reaction of WO3 in H2O2 with oxazine-type ligand, 2-(2′-hydroxyphenyl)-5,6-dihydro-1,3-oxazine (Hphox). The complex was characterized by FTIR, 1H NMR and elemental analysis. The single-crystal X-ray diffraction studies revealed a seven coordinate tungsten center with a distorted octahedral geometry. The [WO(O2)2(phox)] complex was applied as a catalyst in efficient, and selective oxidation of sulfide to sulfoxide using 30% H2O2 or UHP as oxidants. This catalyst showed excellent catalytic activities and high selectivities in producing a variety of aryl and alkyl sulfoxides under mild conditions. To get...