Organic synthesis facts for kids

Organic synthesis is a special part of chemical synthesis. It's all about making new organic compounds. These are special chemicals that contain carbon. Scientists use organic reactions to build these compounds.

Organic molecules can be very complex. Because of this, making them is a super important part of organic chemistry. There are two main areas in organic synthesis: total synthesis and methodology.

What is Total Synthesis?

Total synthesis means building a complex organic compound from scratch. You start with simple chemicals that are easy to get. These can be from oil (petrochemicals) or natural sources.

Sometimes, scientists build the molecule step-by-step. This is called a linear synthesis. Each step creates a new chemical called an synthetic intermediate. For more complex molecules, they might use a convergent synthesis. This is like building different parts of a puzzle separately. Then, they combine these "pieces" to make the final product.

Robert Woodward is known as the father of modern organic synthesis. He won the Nobel Prize in Chemistry in 1965. He made many complex molecules, like strychnine in 1954. Other famous examples include the synthesis of Taxol by different scientists.

How New Methods Are Developed

Each step in making a chemical involves a chemical reaction. Scientists need to choose the right chemicals (called reagents) and conditions. This helps them get a lot of the desired product. They also want the product to be very pure.

Sometimes, a way to make a chemical already exists. Scientists will use that method. But often, they need to make new chemicals that have never been made before. For this, they use general methods developed by researchers. These methods must give high amounts of the product. They also need to work for many different starting chemicals.

Developing new methods usually has three main steps:

• Discovery: Scientists use their knowledge of how chemicals react. They find new ways to make reactions happen.
• Optimization: They test one or two starting chemicals. They try different temperatures, solvents, and reaction times. They keep trying until they find the best conditions. This helps them get the most product.
• Scope and Limitations: Finally, they see how well the new method works. They try it with many different starting materials. This shows them what the method can and cannot do.

Sometimes, a total synthesis is done to show how useful a new method is. Big industries use this research. This includes companies that make polymers (like plastics) and medicines.

Making Specific Molecules: Asymmetric Synthesis

Most complex chemicals found in nature are "chiral". This means they can exist in two forms, like your left and right hands. These two forms are called enantiomers. Each enantiomer can have different effects. For example, one might be a helpful medicine, while the other does nothing or is even harmful.

In the past, scientists often made a mixture of both enantiomers. This was called a racemic mixture. Then, they had to separate the two forms.

Later, chemists found ways to make only one enantiomer. This is called asymmetric synthesis. Early examples include reactions developed by Karl Barry Sharpless, William S. Knowles, and Ryōji Noyori. They shared the Nobel Prize in Chemistry in 2001 for their work.

These new methods gave chemists more choices. They could start with pure enantiomers. They also learned to control the shape of the molecule as they built it. This is called stereocontrol. It meant they could make the final product as one pure enantiomer. They didn't need to separate it later.

Designing a Synthesis

Elias James Corey created a more organized way to plan chemical syntheses. He called it retrosynthetic analysis. He won the Nobel Prize in Chemistry in 1990 for this idea.

In this method, scientists plan backwards from the final product. They imagine breaking the molecule down into simpler pieces. They use special arrows (drawn as: =>) to show this. This means "is made from". Computer programs have even been written to help design syntheses this way.

See also

In Spanish: Síntesis orgánica para niños