Friedrich August Kekulé was born in Darmstadt, Germany on september 7, 1829. In 1856 he started his career as private teacher in Heidelberg, Germany. In 1858 he was nominated professor at the Universuty of Gent, Belgium.
The field of organic chemistry was first put on a sound basis by Kekulé with his determination that carbon has a valence of 4. Kekulé also found that of the four bonds for each carbon atom, one of the bonds can link to another carbon atom, permitting carbon-based molecules to form chains. Kekulé's recognition of such structures provided an explanation for isomers and other phenomena. His vision of the benzene ring from 1861 (originating from a dream where a snake ate its own tail) became the basis for the chemistry of aromatic compounds.