The significance of vitamin A is credited to the results of work dating back to 1906. It was first synthesized, however, in the laboratory in 1947 by two Dutch chemists, Jozef Ferdinand Arens and David Adriaan van Dorp.
Kuhn and Morris reported the synthesis of vitamin A in 1937. However, their route provided a sample with only 7.5% biological activity due to the impure intermediate β-C15-aldehyde. It is recorded that the Kuhne-Morris synthesis was repeated by several groups over the following years, unfortunately to no avail.
Arens and van Dorp published the first route in 1946, and critical contributions have been made by a number of scientists since, benefitting from fruitful collaborations between industry and academia.
Arens and van Dorp began their investigations into vitamin A by synthesizing various compounds with vitamin A activity, namely vitamin A acid.
The derivative was actually obtained by synthesis from β -ionone, and is a crystalline acid melting at 181.5°C and having an ultraviolet absorption spectrum maximum at 3430 A. On 9 August 1947, Nature published a short article announcing the reduction of aldehyde to alcohol under mild conditions. The synthesis of vitamin A had been achieved.
Several months later, researchers of Hoffmann-La Roche published an article in Helvetica Chimica Acta in which they described their synthesis, which does lead to pure, crystalline, vitamin A.
Synthesis of vitamin A
