Fully stereodivergent dual-catalytic α-allylation of protected α-amino- and α-hydroxyacetaldehydes is achieved through iridium- and amine-catalyzed substitution of racemic allylic alcohols with chiral enamines generated in situ. The operationally simple method furnishes useful aldehyde building blocks in good yields, more than 99% ee, and with d.r. values greater than 20:1 in some cases. Additionally, the γ,δ-unsaturated products can be further functionalized in a stereodivergent fashion with high selectivity and with preservation of stereochemical integrity at the Cα  position.

The first total synthesis of the marine polyketide (±)-hippolachnin A has been achieved in nine linear steps and an overall yield of 9%. Rapid access to the oxacyclobutapentalene core structure was secured by strategic application of an ene cyclization.

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The iridium-catalyzed asymmetric allylic substitution under biphasic conditions is reported. This approach allows the use of various unstable and/or volatile nucleophiles including hydrazines, methylamine, tbutyl hydroperoxide, N-hydroxylamine, α-chloroacetaldehyde and glutaraldehyde. This transformation provides rapid access to a broad range of products from simple starting materials in good yields and up to >99% ee and 20:1 d.r. Additionally, these products can be elaborated efficiently into a diverse set of cyclic and acyclic compounds, bearing up to four stereocenters.

A method for the enantio- and chemoselective iridium-catalyzed O-allylation of oximes is described. Kinetic resolution in an intramolecular setting provides enantioenriched oxime ethers and aliphatic allylic alcohols. The synthetic potential of the products generated with this method is showcased by their elaboration into a series of heterocyclic compounds and the formal synthesis of glycoprotein GP IIb-IIIa receptor antagonist (−)-roxifiban. Preliminary mechanistic experiments and computational data shed light on the remarkable chemoselectivity of the reaction.