Enantioselective Bayhs-Hillman

Gausepohl R, Buskens P, Kleinen J et ril (2006) Highly enantioselective aza-BayHs-Hillman reaction in a chiral reaction medium. Angew Chem Int Ed 45 3689-3695... 

The P-chirogenic organocatalysts 294 and 295 were found to promote the enantioselective aza-Morita-Bayhs-Hillman reaction of ketimines derived from acyclic a-keto esters. In the P-chirogenic organocatalyzed aza-Morita-Baylis-Hillman reactions, a,a-disubstituted a-amino acid derivatives 296 were obtained in high yields and with high enantioselectivities (up to 97% cc) (Scheme 98) [195]. 

The synthetic route to the structurally related bis-thioureas of type 32 from (R)-5,5, 6,6, 7,7, 8,8 -octahydro-l,T-binaphthyl-2,2 -diamine was reported by Shi. The effectiveness of the acid-base synergistic catalysis of parent 32a and N,N-diisopropylethylamine was verified by application to the asymmetric Henry reaction of nitromethane with aromatic aldehydes (Scheme 7.57) [86]. Moreover, the Morita-Bayhs-Hillman reaction between 2-cyclohexen-l-one or 2-cyclopenten-1-one and aromatic aldehydes was found to proceed with moderate to good levels of enantioselectivity under the catalysis of 32b, which has additional 3,5-bis(trifluoromethyl)phenyl groups at the 3,3 -positions of the octahydrobinaph-thyl backbone, and l,4-diazabicyclo[2.2.2]octane (DABCO) (Scheme 7.57) [87]. 

The Binol-based bifunctional catalyst 7 was used by Sasai and coworkers in 2005 in the enantioselective aza-Morita-Bayhs-Hillman reaction of a,P-unsaturated... 

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