Green Chemistry

Green Chemistry is the utilization of a set of principles that reduces or eliminates the use or generation of hazardous substances in the design, manufacture, and application of chemical products

12 Principles of Green Chemistry:

1. Prevent Waste

Design chemical syntheses to prevent waste. Leave no waste to treat or clean up.

2. Maximize atom economy

Design syntheses so that the final product contains the maximum proportion of the starting materials. Waste few or no atoms.

3. Design less hazardous chemical syntheses

Design syntheses to use and generate substances with little or no toxicity to either humans or the environment.

4. Design safer chemicals and products

Design chemical products that are fully effective yet have little or no toxicity.

5. Use safer solvents and reaction conditions

Avoid using solvents, separation agents, or other auxiliary chemicals. If you must use these chemicals, use safer ones.

6. Increase energy efficiency

Run chemical reactions at room temperature and pressure whenever possible.

7. Use renewable feedstocks

Use starting materials (also known as feedstocks) that are renewable rather than depletable. The source of renewable feedstocks is often agricultural products or the wastes of other processes; the source of depletable feedstocks is often fossil fuels (petroleum, natural gas, or coal) or mining operations.

8. Avoid chemical derivatives

Avoid using blocking or protecting groups, or any temporary modifications if possible. Derivatives use additional reagents and generate waste.

9. Use catalysts, not stoichiometric reagents

Minimize waste by using catalytic reactions. Catalysts are effective in small amounts and can carry out a single reaction many times. They are preferable to stoichiometric reagents, which are used in excess and carry out a reaction only once.

10. Design chemicals and products to degrade after use

Design chemical products to break down to innocuous substances after use so that they do not accumulate in the environment.

11. Analyze in real-time to prevent pollution

Include in-process, real-time monitoring, and control during syntheses to minimize or eliminate the formation of byproducts.

12. Minimize the potential for accidents

Design chemicals and their physical forms (solid, liquid, or gas) to minimize the potential for chemical accidents, including explosions, fires, and releases to the environment.

Aromatic Substitution reactions (S_NAr)

S_NAr rean – F displacement

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S_NAr rean – Cl displacement

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Amide to other Functional Groups

LAH or LiAlH₄ reduction

BH₃.THF (Borane THF) reduction

Using BH₃.Me₂S (BMS reduction)

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Hofmann rearrangement (for 1^o amide only)

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Using POCl₃

Using SOCl₂

Using T3P

Using TFAA

Using Cyanuric chloride

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Amide hydrolysis under basic condition

Amide hydrolysis under acidic condition

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• LAH or LiAlH₄ reduction
• BH₃.THF (Borane THF) reduction
• Using BH₃.Me₂S (BMS reduction)

Dess-Martin Oxidation (Dess-Martin Periodinane, DMP)
Using PCC (Pyridinium Chlorochromate)
Using PDC (Pyridinium Dichromate)
Swern Oxidation (DMSO, Oxalyl chloride)
Pfitzner-Moffatt Oxidation (DMSO, DCC, acid)
Using MnO₂
Corey-Kim Oxidation (DMSO, NCS)
Swern Oxidation variant (DMSO, TFAA)
Parikh–Doering oxidation (DMSO, py.SO₃)