Costin D. Neniţescu (Romanian pronunciation: [kosˈtin neniˈt͡sesku]; July 15, 1902 – July 28, 1970) was a prominent Romanian chemist, and a professor at the Polytechnic University of Bucharest. He was a member of the Romanian Academy, a corresponding member of the German Academy of Sciences in Berlin, and a member of the Leopoldina Academy of Natural Scientists in Halle-Saale.
After completing in 1920 his secondary studies at Gheorghe Lazăr High School, Neniţescu continued his studies at the Polytechnic Institute in Zürich and Ludwig Maximilians University in Munich, where he was one of the favorite students of Hans Fischer.[1]
He studied Friedel-Crafts-like reactions in the series of aliphatic hydrocarbons, the mechanism of the isomerization of cyclobasics, the halogen migration in cycles and chains, reactions induced by carbonium ions, and others. He identified a group of naphthenic acids in Romanian crude oil. He searched for ways of obtaining cyclobutadiene, while explaining the chemistry of this unstable substance and isolating its dimers.
His research interests were also in the oxidation of open-chain and aromatic hydrocarbons with chromic acid and chromic oxychloride. He found new methods for the synthesis of pirilium salts, of carbenes, triptamine, serotonine, two new syntheses for the indole nucleus, and a new method of polymerisation of ethylene.
His research was substantiated in more than 200 papers. His remarkable technical and scientific activity helped develop the chemical industry in Romania.
In his honor, the chemistry contest "C.D. Nenitescu" is organized yearly at the Polytechnic University of Bucharest.