what is the diffrence between stereo- and chiralcenter?


what is the diffrence between stereo- and chiralcenter?

In: 1

Very little. A molecule is chiral if it can’t be superimposed on its mirror image. This is quite common in organic chemistry where a carbon bonded to four different groups is a chiral carbon (e.g. CHFClBr – there are two ways of arranging the four atoms around the carbon: mirror images and one can’t be turned into the other without breaking a bond and rearranging the order: a process called racemising).

These mirror images are called stereoisomers or sometimes optical isomers as the two have the effect of causing polarised light to rotate in opposite directions as it passes them.

Some famous examples of chiral molecules are cholesterol (one stereoisomer is ‘bad’, the other isn’t, and thalidomide which was widely prescribed as a treatment for morning sickness in the mid-20th century. While it did help with the symptoms, one of the isomers was mutagenic and caused birth defects. Unfortunately the compound racemises inside the human body so even giving someone only the ‘safe’ isomer wouldn’t alleviate the problem.