Bio-based Chemicals Used As Solvents And Catalysts In Organic Synthesis

With the development of contemporary organic chemistry, there has been a growingchallenge of solving the energy consumption and protecting the environment. In this regard, toaddress the problem in many synthetic organic processes, tremendous efforts have been devotedtoward improving efficiency, reducing the energy consumption and reducing energy. Greenchemistry includes12areas: reducing waste, atom efficiency, reduce toxic substances, productsafety production, use non-toxic solvents, reduce energy, use of renew able raw materials,synthetic route is shorter, catalytic reagents without using chemo metrics, biodegradable products,pollution prevention, process safety.In the course of the revolution of green chemistry, solvents and catalysts play a vital role,they can accelerate the reaction, improve the reaction yield. However, Considering the use oftraditional organic solvents which are toxic, volatile and difficult to recycling and the limitationof common catalysts including acid and alkali catalysts, metal catalysts, transition metal oxidecatalyst, complexing catalyst which are expensive, preparation process trival, environmentalpollution, harsh reaction conditions. So, those make the traditional solvent and catalyst isfollowing the concept of green chemistry. For this stage, the use of solvents and catalysts playeda central role in green chemistry. This paper describes representative bio-based chemicals used assolvents and catalysts widely used in organic synthesis. They are low cost, low toxicity,environmentally friendly, biocompatible, biodegradable.Bio-based chemicals used as solvents and catalysts in organic synthesis, greatly reducing theenvironmental pollution and energy consumption, and thus a wide range of applications andresearch in this field. Bio-based materials are inexpensive, low toxicity, biodegradable andenvironmentally friendly. These features make them more and more attractive in catalysis,bio-transformation and organic synthesis. The latest progress of bio-based chemicals such aschitosan, gluconic acid, lactic acid, glycerol and mixtures of low melting point material havebeen proposed as safer, sustainable, renewable, and biodegradable catalysts or solvents forcatalysis and organic chemistry.First, gluconic acid is a biodegradable, weakly acidic aqueous solution and can promoteorganic reactions to product spirooxindoles. We conducted the model reaction of isatin,cyclohexane-1,3-dione and barbituric acid in100oC to synthesis of functionalized spirooxindoles. Gluconic acid was used as an efficient and reusable promoting medium topromote the reation.Then, we have developed a highly efficient and greener approach for the synthesis ofpyrano derivatives using meglumine as an inexpensive, biodegradable catalyst. we report a facile,one-pot, three-component process for the synthesis of functionalized pyrans from the reaction ofaldehydes, isatin derivatives, or acenaphthenequinone with enolizable C H activated compoundsand alkylmalonates in the presence of meglumine at room temperature.Furthermore, pyranopyrazole derivatives have anti-cancer, anti-bacterial, anti-inflammatory,insecticidal and other biological activity, widely used in the medical and pharmaceutical fields.We selected benzaldehyde, hydrazine hydrate, malononitrile, ethyl acetoacetate as modelsubstrates to product pyranopyrazoles. The use of meglumine leads to an improved protocol interms of compatibility with environment, reaction time, and yield when compared with othercatalyst.The last, functionlized dihydropyridines are an important class of biologically activeheterocycles. Functionlized dihydropyridines have attracted considerable attention because oftheir wide variety of biological activities, including anti-hypertension, antioxidant, anticancer,antitumor activity. We now report the synthesis of functionlized dihydropyridines by a one-potreaction of aldehydes, amine, malononitrile, dimethylacetylenedicarboxylate in the presence ofmeglumine under ethanol aqueous solution.In summary, the application of bio-based chemicals in organic chemistry was discussed. Weuse glucose acid and meglumine as bio-based chemicals to start this experiment. We found thatgluconic acid, meglumine can increase the reaction rate, environmental pollution, less energyconsumption in the synthesis of spirooxindoles derivatives, pyran derivatives, pyrano-pyrazolederivatives, dihydropyridine derivatives.