Rauhut-Currier reaction

The Rauhut-Currier reaction is an organic reaction describing the dimerization or isomerization of enones by action of an organophosphine of the type R3P. The reaction mechanism is essentially that of the related and better known Baylis-Hillman reaction (DABCO not phosphine, carbonyl not enone) but the Rauhut-Currier reaction actually predates it by several years.

The original 1963 reaction described the dimerization of the ethyl ester of acrylic acid to the corresponding diester of 2-methylene-glutaric acid with tributylphosphine in acetonitrile:



The reaction type has been utilized in an intramolecular isomerization of di-enones to form cyclopentenes:



A similar reaction by asymmetric synthesis organocatalyzed by a protected cysteine and potassium tert-butoxide afforded a cyclohexene with 95% enantiomeric excess:



In this reaction the phosphine is replaced by the thiol group of cysteine but the reaction is the same.