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Über dieses Buch

Heterogeneously catalyzed selective oxidations of alcohols is a highly topical field. The first chapter of this brief describes the importance of the selective oxidation of alcohols and advantages of heterogeneous catalysts over conventional catalysts, use of environmentally benign oxidants, and the design of selective catalysts by tailoring of polyoxometalates at the molecular level. Chapter 2 describes synthesis, characterization 11-molybdophosphate based supported materials and their use as heterogeneous catalysts for oxidation of alcohols with molecular oxygen under solvent free mild reaction condition. ZrO2, Al2O3, MCM-41 and zeolite Hβ were used as supports. Chapter 3 describes synthesis, characterization of transition metals (Mn, Co, Ni, Cu)- substituted phosphomolybdates and their use as heterogeneous catalysts for oxidation of alcohols with molecular oxygen under solvent free mild reaction condition. Chapter 4 describes conclusive remarks for present catalytic systems.

Inhaltsverzeichnis

Frontmatter

Chapter 1. Introduction

Abstract
Chemical industries have contributed to worldwide economic development over the past century and chemical products make an enormous contribution to the quality of our lives. At the same time, the manufacturing processes of chemicals have also led to vast amounts of wastes. Hence, today the reduction/elimination of these wastes is a central issue. Towards the same, awareness within the fine chemicals and pharmaceutical industry to improve the environmental and production costs of synthesis over the release of waste products and toxins into the environment has been increased tremendously. A sustainable society is one that meets the needs of the current generation without sacrificing the ability to meet the needs of future generations. Sustainable development is a strategic goal. It can be reached using various approaches, and this is where green chemistry comes in.
Anjali Patel, Soyeb Pathan

Chapter 2. Oxidation of Alcohols Catalyzed by Supported Undecamolybdophosphate

Abstract
Synthesis and stabilization of undecamolybdophosphate (PMo11) as well as its characterization was explained. Also, synthesis and characterization of series of heterogeneous catalysts comprising PMo11 and different supports (ZrO2, Al2O3, MCM-41 and zeolite-Hβ) and their use as heterogeneous catalysts for solvent free oxidation of alcohols with molecular oxygen and TBHP as a radical initiator was described. The influence of different parameters on the conversion as well as the selectivity was investigated on oxidation of benzyl alcohol. Further, oxidation of various alcohols such as cyclopentanol, 1-hexanol and 1-octanol over supported PMo11 was presented under optimized conditions. All the catalysts are found to be efficient especially in achieving higher selective toward desire product and high turnover numbers. Regeneration study showed that the catalysts can be regenerated and reused without any significant loss in the catalytic activity.
Anjali Patel, Soyeb Pathan

Chapter 3. Oxidation of Alcohols Catalyzed by Transition Metal Substituted Phosphomolybdates

Abstract
Synthesis and characterization of mono transition metal-substituted Keggin-phosphomolybdates, PMo11M (M = Mn, Co, Ni, Cu) as well as their use as efficient catalysts for aerobic oxidation of alcohols in presence of TBHP as a radical initiator was explained. Optimization of reaction condition was also elucidated for oxidation benzyl alcohol as a model reaction. Moreover, oxidation of various alcohols such as cyclopentanol, 1-hexanol and 1-octanol with PMo11M was also presented under optimized conditions. All the catalysts showed good catalytic activity with excellent selectivity for the desired products as well as a higher TON. The catalytic activity of recycled catalysts was also described and it was found that catalysts are stable under present reaction conditions. The system not only catalyzes the reaction but also avoids the use of organic solvents as it was carried out under solvent free conditions. A probable reaction mechanism was also explained for the oxidation of alcohols.
Anjali Patel, Soyeb Pathan

Chapter 4. Conclusive Remarks

Abstract
n the present book, we have discussed an overview of a part of research conducted in our group on the development of heterogeneous catalysts for oxidation reactions under solvent free green reaction conditions. Unique properties of POMs permit designing at molecular level. Special attention was focused on the designing and application of POMs based on phosphomolybdates. As a part of development of new phosphomolybdates materials (1) synthesis and isolation of PMo11 was described. Also, stabilization of PMo11 was successfully done by supporting it to suitable supports (2) one-pot synthesis of PMo11M (M = Mn, Co, Ni, Cu) was also discussed. These procedures open up new synthetic routes for development of other POMs based material.
Anjali Patel, Soyeb Pathan
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