Preparing lactic acid/lactate, useful e.g. as monomer for plastics, and in cosmetics and food products as food additives, comprises reacting 3-carbon containing organic starting compound, in presence of transition metal catalyst

: Danzig, J.; Fastabend, A.; Grän-Heedfeld, J.; Kraft, A.

Abstract
(A1) Gegenstand der Erfindung ist ein katalytisches Verfahren zur Herstellung bzw. Gewinnung von chemischen Grundstoffen aus nachwachsenden Rohstoffen, insbesondere von 2-Hydroxypropansaeure (Milchsaeure) oder Salzen der Milchsaeure (Lactaten), ausgehend von Glycerinen oder Zuckern.

 

EP 2100871 A1 UPAB: 20091001 NOVELTY - Preparation of 2-hydroxy propanoic acid (lactic acid) or its salts (lactate), comprises reacting at least a 3 carbon atom containing organic starting compound, which is a primary alcohol (I) and/or an aldehyde (II), where (I) and/or (II) exhibits a hydroxyl group in alpha -position to the primary alcohol function and/or to the aldehyde group, and a hydroxyl- or ether group in beta -position to the primary alcohol function and/or to the aldehyde group, in the presence of a transition metal catalyst. USE - The lactic acid or lactate is useful: as a monomer for plastics (polylactic acid or polylactide) or as a basic component for solvents orsurfactants; and in various products, such as in cosmetics, food products as food additives and agrochemicals. ADVANTAGE - The process provides lactic acid or lactate with good to high selectivity and with high yield, without any significant caramelization of the parent compound. The resulting by-product (1,2-propanediol) can be recycled to lactic acid.