What is "chiral"?

Question

jeopardy

Answer 1

a molecule not being superimposable on its mirror image

Answer 2

Having been closely involved with a chiral chemistry company in the past, I'll try to make it simple to supplement the other good answers here.

Drugs work in the body like a key going into a lock. If the key is upside down, it won't work (or possibly, it may open a very bad lock elsewhere in the body).

Chiral molecules have left hand and right hand versions, just like up and down keys. For a drug to work properly, it must be the correct version.

For the technical details, chirality occurs when there are 4 separate linkages attached to a carbon atom. They have very similar physical properties and it is diffiult to separate them when mixed together (called a racemic mixture). The best bet is to use a chiral catalytic technology (small molecule or enzyme) to make only the desired version from the start.

Answer 3

chirality refers to asymmetry.

your hands are chiral. they are mirror images that you cant superimpose. (left and right gloves don't match)

in a large organic molecule people will talk about chirality centers. the chiral center is the location where the chirality arises. if a tetrahedral atom is bonded to 4 different substituents then it is most likely a chirality center. the easiest example is to take a model kit and put 4 different color balls on a tetrahedral ball then make a mirror image of that model. they cant be lined up with all 4 balls facing in the same direction.

the 2 mirror image molecules are called enantiomers

if there are multiple chirality centers you can get isomers that are not mirror images these pairs that are not mirror images are diastereomers.

at each chirality center hold the lightest substituent in the back then look at the order of the heaviest to lightest of the other 3 substituents. if they go clockwise the center is called "R" counterclockwise is "L"

is that enough? i don't want to ramble on :P

Answer 4

The term chiral (pronounced /ˈkaɪɹ(ə)l̩/) is used to describe an object which is non-superimposable on its mirror image. In terms of chemistry, these objects are usually molecules. The study of chiral molecules and associated phenomena is a very active area.

A molecule is chiral if it cannot be superimposed on its mirror image (see diagram); the two mirror images of such a molecule are referred to as enantiomers. A mixture of equal amounts of the two enantiomers is said to be a racemic mixture. Chirality is of interest because of its application to stereochemistry in inorganic chemistry, organic chemistry, physical chemistry and biochemistry.

Answer 5

The mirror image of an object or shape.