# How many chiral centers does Phenylsuccinic acid have?

## How many chiral centers does Phenylsuccinic acid have?

three chiral centers
Formation of a salt containing three chiral centers. This one is a diastereomer of the salt in the previous picture. If a racemic mixture of phenylsuccinic acid is used, but pure (-)-proline is added, two possible diastereomers result. One chiral center, in the proline, is always the same.

### How to isolate phenylsuccinic acid?

To isolate (–)-phenylsuccinic acid, evaporate the filtrate after filtering out the (+)-salt. To simply demonstrate that (–)-phenylsuccinic acid was in the filtrate, stir the remain- ing residue with 10 mL of 6M HCl for 10 min.

What is the melting point of Phenylsuccinic acid?

166-168° C
Melting Point : 166-168° C (lit.)

How is optical purity calculated?

Optical purity % = 100 * (- 9.2o / – 23.1o) = 40 % ie there is a 40% excess of R over S. This corresponds to a mixture of 70% R and 30% S. How do you get this quickly? Well, if there is a 40% excess of R, then the 60% leftover must be equal amounts of both R and S ie.

## How do you measure optical purity?

### Is optical rotation a physical property?

Fortunately, there is one physical property in which enantiomers differ: their ability to rotate plane-polarized light. The ability of a solution to rotate plane-polarized light in this fashion is called optical activity, and solutions which have this ability are said to be optically active.

What is optical purity and enantiomeric excess?

Enantiomeric Excess The “optical purity” is a comparison of the optical rotation of a pure sample of unknown stereochemistry versus the optical rotation of a sample of pure enantiomer. It is expressed as a percentage. If the sample only rotates plane-polarized light half as much as expected, the optical purity is 50%.

What does optical rotation tell you?

Optical activity is measured using a polarized source and polarimeter. This is a tool particularly used in the sugar industry to measure the sugar concentration of syrup, and generally in chemistry to measure the concentration or enantiomeric ratio of chiral molecules in solution.

## Is optical rotation and specific rotation the same?

Optical rotation is the rotation of plane-polarized light when a light beam is directed through certain materials. Specific rotation gives the angle of rotation of plane-polarized light by a certain compound at a certain temperature. This is the key difference between optical rotation and specific rotation.