Tetramethylbenzenes

The tetramethylbenzenes form a group of substances, whose structure consists of a benzene ring with four methyl groups (- CH3) as a substituent in the chemical industry. Due to their different arrangement of three structural isomers arise with the molecular formula C10H14. They are mainly known under their common names Prehnitol (1,2,3,4 -tetramethyl benzene ), isodurene ( 1,2,3,5 -tetramethyl benzene ) and durene ( 1,2,4,5 -tetramethyl benzene ). They also belong to the group of C4 - benzenes.

History

The durene was discovered in 1870. The discoverer report that it was the first hydrocarbon of the benzene series, which is solid at room temperature. The name was therefore selected (hard =) after the Latin durus.

The Prehnitol was discovered in 1886. It can be converted by oxidation into prehnitic. This acid crystallizes in a similar manner as the mineral occurring in South Africa Prehnite and was therefore named after him. The namesake for the Prehnitol was Adolf von Baeyer. The mineral in turn was named after a Supreme by Prehn.

Properties

The boiling points of the three isomers are close together, while they have different melting points clearer. Durene which has the highest melting point of 79.2 ° C. Due to its symmetry; it is a solid, in contrast to the other two isomers.