Calcium Chloride catalyzed Intramolecular Oxa Michael addition of 2’-Hydroxychalcone to Flavanone

Calcium Chloride faciled Intramolecular Oxa addition of 2’-Hydroxychalcone to Flavanone

Diastereoselective synthesis of pitavastatin calcium via bismuth-catalyzed two-component hemiacetal/oxa-Michael addition reaction.

An efficient and concise asymmetric synthesis of pitavastatin calcium (1) starting from commercially available (S)-epichlorohydrin is described. A convergent C1 + C6 route allowed for the assembly of the pitavastatin C7 side chain via a Wittig reaction between phosphonium salt 2 and the enantiomerically pure C6-formyl side chain 3. The 1,3-syn-diol acetal motif in 3 was established with excelle...

Phosphine-catalyzed regioselective Michael addition to allenoates.

The first phosphine catalysed Michael addition of arylcyanoacetates to allenoates has been developed, and the β-selective products with a quaternary center were obtained in excellent yields. This unusual regioselectivity may open new opportunities to access interesting molecular structures.

Antibody-catalyzed asymmetric intramolecular Michael addition of aldehydes and ketones to yield the disfavored cis-product.

The development of new catalytic asymmetric reactions continues to be a major goal in organic chemistry. Here we report a novel antibody-catalyzed intramolecular Michael addition of aldehydes and ketones to enones. The reaction is enantioselective and diastereoselective with a high ee value and cis/trans ratio. This is the first example of asymmetric intramolecular Michael addition of ketones. ...

N-heterocyclic carbene-catalyzed aza-Michael addition.

Aza-Michael addition of amines, including aromatic and aliphatic amines, with α, β-unsaturated ketones was realized employing N-Heterocyclic Carbene (NHC) as organocatalyst, yielding β-amino ketones with up to 98% yield.