High Selective Oxidation of Alcohols Based on Trivalent Ion (Cr³⁺and Co³⁺) Complexes Anchored on MCM-41 as Heterogeneous Catalysts

Abstract

Cr(III) and Co(III) complexes with acetylacetonate were anchored onto a mesoporous MCM-41 through Schiff condensation. The materials were characterized by XRD, FT-IR, BET, CHN and ICP techniques. Elemental analysis of samples revealed that one C=N bond was formed through Schiff condensation on MCM-41 surface. The catalysts were tested for the alcohol oxidations using t-butyl hydroperoxide (TBHP) and H 2 O 2 as oxidant. The catalytic experiments were carried out at both room temperature and reflux condition. Various solvents such as dichloromethane, acetonitrile and water were examined in the oxidation of alcohols. Among the different solvents, catalytic activity is found more in acetonitrile. Further, the catalysts were recycled three times in the oxidation of alcohols and no major change in the conversion and selectivity is observed, which shows that the immobilized metal-acetylacetonate complexes are stable under the present reaction conditions.

Synthesis, characterization and study of catalytic activity of Silver doped ZnO nanocomposite as an efficient catalyst for selective oxidation of benzyl alcohol

“…Actually, when H 2 O 2 was utilized for the oxidation of alcohols, most of H 2 O 2 molecules were decomposed into O 2 and the reaction time was prolonged. 60 3.3f Reusability of catalytic systems: The reusability of the synthesized catalysts is a significant factor from environmental and economical points of view. In heterogeneous catalysts the leaching of metal is a main problem, which leads to loss of catalyst activity on subsequent uses.…”

“…Nano-sized Zinc oxide an inexpensive, non-toxic and easily available Lewis acid catalyst is another semiconductor metal oxide which has been widely used as catalyst in organic transformations. 47,[54][55][56] In our previous published research works, [57][58][59][60][61][62][63] we synthesized some catalytic systems and activities of the prepared catalysts were described in relation to different reactions. In the present work, we investigated the synthesis of efficient Ag-ZnO nanocomposits for oxidation of benzylic alcohols to the corresponding aldehydes or ketone under reflux and microwave irradiation.…”

Rice husk derived nanosilica supported Cu(ii) complex: an efficient heterogeneous catalyst for oxidation of alcohols using TBHP

“…It is due to its poor solubility in the reaction medium. [38][39][40] In solvent-free condition, the yield of product is trace amount (Table 2, entry 10). The effect of catalyst amount on oxidation of 1-phenyl ethanol was also investigated.…”

Effect of preparation temperature and ions doping on size, morphology and catalytic activity of Co-B amorphous nano catalyst

“…Some of them include NbCl 5 /In [21], Cu [22], Ag@SBA-15 [23], Au/PMMA [24] and Ag-MCM-41 [25]. In continuation of our study on oxidation of alcohols [26], photodegradation of 4-NP [27] methyl orange and methylene blue [28] we tried to reduce of 4-NP over metal boride nano catalysts. Also, previously we have synthesized Co-La-Zr-B quaternary amorphous nano alloy [29], PVP stabilized crystalline phase of Co-La-Zr-B [30] and oleic acid stabilized Co-La-Zr-B [31] for hydrogen generation through hydrolysis of sodium borohydride.…”