Organic Chemistry: Current Research
Open Access

An Overview on Sustainable Strategies of Green Synthesis

Yoichi Le^{* *}Correspondence: Yoichi Le, Department of Materials and Applied Chemistry, Nihon University, Tokyo, Japan, Email:

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Description

Green synthesis, also known as sustainable synthesis or eco-friendly synthesis is an approach to chemical synthesis that prioritize minimizing the environmental impact of chemical reactions and processes. The goal of green synthesis is to reduce the use of hazardous chemicals, energy consumption, waste generation, and overall resource depletion while maximizing efficiency and sustainability.

Organic compounds are a broad class of chemical compounds that contain carbon atoms bonded to hydrogen, oxygen, nitrogen, sulfur, and other elements. Carbon is the central element in organic chemistry, and it forms the foundation of these compounds. Organic compounds are known for their diverse structures and functions, making them essential in biology, chemistry, and industry. Examples of organic compounds:

• Hydrocarbons with one or more carbon-carbon triple bonds. Example: Ethyne (acetylene, C2H2).

• Organic compounds containing the hydroxyl (-OH) functional group bonded to a carbon atom. Example: Ethanol (C2H5OH), methanol (CH3OH).

• Organic compounds with the carbonyl group (C=O) bonded to a hydrogen atom and a carbon atom. Example: Formaldehyde (methanal, CH2O), acetaldehyde (ethanal, CH3CHO).

Steps involved in green synthesis

Atom economy: Green synthesis strives to maximize the incorporation of reactants into the final product, minimizing the generation of byproducts and waste. Reactions with high atom economy are preferred.

Solvent selection: Water is often the preferred solvent due to its environmental benignity. Green solvents, such as supercritical CO2 or ionic liquids, may also be used to reduce the environmental impact of reactions.

Catalysis: The use of catalysts allows reactions to occur under milder conditions, reducing energy consumption and waste generation. Homogeneous and heterogeneous catalysts are employed to facilitate organic transformations.

Renewable feedstocks: Green synthesis promotes the use of renewable feedstocks, such as biomass-derived chemicals, to replace non-renewable resources like petroleum-based starting materials.

Biocatalysis: Enzymes and microorganisms can be employed as biocatalysts in organic synthesis, offering high specificity and sustainability. Enzymatic reactions often occur under mild conditions and generate fewer by-products.

Microwave and ultrasound activation: These techniques can accelerate reactions, allowing them to proceed more efficiently and with shorter reaction times, reducing energy consumption.

Flow chemistry: Continuous flow reactors enable precise control of reaction conditions and efficient mixing, reducing the environmental impact and improving selectivity.

Waste minimization: Green synthesis focuses on the reduction or elimination of hazardous waste. Techniques like recycling and separation of reactants and products are employed to minimize waste generation.

Safety considerations: Green synthesis prioritizes safety by avoiding the use of highly toxic or hazardous chemicals and by-products.

Methods of green synthesis

Suzuki-miyaura cross-coupling: This reaction involves the coupling of aryl halides with boronic acids, catalyzed by palladium. It is widely used in pharmaceutical and materials chemistry.

Click chemistry: Reactions like the Huisgen 1,3-dipolar cycloaddition are considered "click chemistry" due to their efficiency, specificity, and minimal byproduct formation.

Biocatalytic transformations: Enzymes like lipases and proteases are used in the synthesis of pharmaceuticals, flavors, and fragrances.

Photochemistry: Reactions activated by light (photoredox catalysis) can be environmentally friendly and energy-efficient.

Ionic liquids: These solvents can replace traditional organic solvents in various reactions and separations, reducing environmental impact.

Conclusion

Organic compounds are essential in biological processes (e.g., DNA, proteins), pharmaceuticals, agriculture, materials science, and many other fields of science and industry. Green synthesis is a multidisciplinary field that integrates principles of chemistry, engineering, and sustainability. Its application has the potential to significantly reduce the environmental impact of chemical processes and make chemical production more sustainable and environmentally responsible.