Alexandre Brethome

An iridium-catalyzed intramolecular asymmetric allylic dearomatization reaction of benzoxazoles, benzothiazoles, and benzimidazoles was developed. The reaction was found to be compatible with a wide range of five-membered-ring electron-deficient heteroaromatic compounds and furnished the corresponding dearomatized heterocycles in high yield with excellent enantioselectivity.

Break up the party: A wide range of electron-deficient nitrogen-containing aromatic compounds with an allylic carbonate side chain underwent intramolecular asymmetric allylic dearomatization in the presence of an iridium catalyst with the chiral ligand Me-THQphos (see scheme). The corresponding dearomatized heterocycles were obtained in high yield with excellent enantioselectivity.

An unprecedented highly regio- and enantioselective rhodium-catalyzed addition of 1,3-diketones to terminal and 1,1-disubstituted allenes furnishing asymmetric tertiary and quaternary all-carbon centers is reported. By applying a Rh^I/phosphoramidite/TFA catalytic system under mild conditions, the desired chiral branched α-allylated 1,3-diketones could be obtained in good to excellent yields, with perfect regioselectivity and in high enantioselectivity. The reaction shows a broad functional-group tolerance on both reaction partners highlighting its synthetic potential.

Rh-Catalysis: A regio- and enantioselective atom-economic catalytic addition of 1,3-diketones to allenes is reported furnishing tertiary and quaternary all-carbon stereocenters under mild reaction conditions. The reaction shows a broad functional-group tolerance and numerous variations on both reaction partners highlight its synthetic utility.