Reformatzki reaction
The Reformatzki reaction is a name reaction in organic chemistry , which was named after its Russian discoverer Sergei Reformatski . The Reformatzki reaction is an organometallic reaction for the formation of carbon-carbon single bonds. The reaction is used to synthesize β- hydroxy esters . To do this, an α- halogenated carboxylic acid ester is reacted with zinc dust and an aldehyde or ketone .
Overview reaction
A ketone (R 1 and R 2 = organyl radical ) or aldehyde (R 1 = H or R 2 = H) reacts with an α- halogenated carboxylic acid ester which has previously been reacted with metallic zinc . The organozinc compound is then hydrolyzed to a β- hydroxy carboxylic acid ester :
The Reformatzki reaction is similar to the Grignard reaction .
mechanism
The Reformatzki reagent , an organic zinc compound similar to Grignard reagents , is obtained from an α-halogenated carboxylic acid ester and zinc dust:
It then reacts with the subsequently added carbonyl component of a ketone or aldehyde . The nucleophilic Reformatzki reagent adds to the carbonyl component and forms an alcoholate which, when worked up in water, yields the desired β-hydroxycarboxylic acid ester.
In contrast to the more reactive Grignard reagents , only ketones and aldehydes react in the Reformatzki reaction, but not esters as carbonyl components.
literature
- S. Reformatzki: New synthesis of diatomic monobasic acids from the ketones , Chem. Ber. 1887 , 20 , 1210. doi : 10.1002 / cber.188702001268
Individual evidence
- ↑ T. Laue, A. Plagens: Name and catchword reactions of organic chemistry . Teubner Verlag, 2006, ISBN 3-8351-0091-2 , p. 281-283 .
- ↑ J. Maiz, A. Arrieta, X. Lopez, JM Ugalde, FP Cossio, K. Facultyatea, EH Unibertsitatea, B. Lecea, Tetrahedron Lett. 1993, 34, p. 6111.
- ↑ Michael B. Smith: March's advanced organic chemistry , John Wiley & Sons, 7th Edition, 2013, pp. 1129-1130, ISBN 978-0-470-46259-1 .
Web links
- organic-chemie.ch: Reformatzki reaction