Catalytic Asymmetric Conjugate Addition/Oxidative Dearomatization Towards Multifunctional Spirocyclic Compounds

Catalytic asymmetric conjugate addition/oxidative dearomatization towards multifunctional spirocyclic compounds.

Catalytic asymmetric conjugate boration of α,β-unsaturated sulfones.

The α,β-unsaturated sulfones are suitable activated olefins in catalytic asymmetric conjugate β-boration. These substrates undergo smooth conjugate addition of bis(pinacolato)diboron [B(2)(pin)(2)] catalyzed by nonracemic Cu(I)-diphosphine complexes to provide, upon subsequent oxidation, β-hydroxy sulfones in good yields and high enantiocontrol.

Phosphoramidites: marvellous ligands in catalytic asymmetric conjugate addition.

The development of an efficient catalytic system for enantioselective carbon-carbon bond formation by 1,4-addition of organometallic reagents (organolithium, Grignard, and organozinc reagents) to enones is a major challenge in organic synthesis. This Account presents the breakthrough realized in this field using chiral phosphoramidite ligands for copper-catalyzed dialkylzinc additions. Applicat...

Catalytic asymmetric conjugate addition of Grignard reagents to chromones.

A highly regio- and enantioselective copper catalysed direct conjugate addition of Grignard reagents to chromones has been developed taking advantage of the reduced reactivity of the resulting magnesium enolates. This methodology tolerates a broad scope of alkyl Grignards including secondary alkyl magnesium reagents as well as functionalised chromones.

Catalytic asymmetric hydroxylative dearomatization of 2-naphthols: synthesis of lacinilene derivatives.

An enantioselective hydroxylative dearomatization of 2-naphthols with oxaziridines has been accomplished using a N,N'-dioxide-scandium(iii) complex catalyst. Various substituted ortho-quinols could be obtained in high yields (up to 99%) and enantioselectivities (up to 95 : 5 er). This methodology could be applied in the synthesis of bioactive lacinilenes in a gram-scale reaction. Based on the e...