Schmitt, Rudolf

Schmitt, Rudolf. "Ueber die Umwandlung der Weinsaure und Apfelsaure in Bernsteinsaure." Annalen der Chemie 114 (1860) 106-11. 

The presently dominant process for the production of salicylic acid is based on the Kolbe-Schmitt synthesis. Hermann Kolbe and E.Lautemann described the reaction of carbon dioxide with sodium phenolate to produce sodium salicylate and its subsequent reaction with sulfuric acid to yield salicylic acid, in 1860. However, as a result of the formation of di-sodium salicylate in this process, only half the phenol was converted into salicylic acid. Rudolf Schmitt modified the synthesis in 1884, by first bringing into contact carbon dioxide with cold, dry sodium phenolate, then heating the mixture under pressure to 120 to 140 °C. 

Professor Adolph Wilhelm Hermann Kolbe (1818-1884), University of Leipzig, Germany. Professor Rudolf Schmitt (1830-1898), University of Dresden, Germany. 

Before he joined BASF, Caro offered his own theoretical investigation into the structure of rosaniline and rosolic acid to Rudolf Schmitt, who in collaboration with Hermann Kolbe had discovered a synthesis of rosolic acid from phenol, oxalic acid and sulphuric acid. Schmitt to Caro, 28 September 1868, SSDM, without signature, in N 93-007. 

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