Organocatalytic Enantioselective Synthesis of Tetrasubstituted α-Amino Allenoates by Dearomative γ-Addition of 2,3-Disubstituted Indoles to β,γ-Alkynyl-α-imino Esters.

摘要: The first asymmetric synthesis of tetrasubstituted α-amino allenoates by a chiral phosphoric acid catalyzed dearomative γ-addition reaction 2,3-disubstituted indoles to β,γ-alkynyl-α-imino esters is reported. This method provides access series highly functionalized allenes featuring quaternary stereocenters in high yields, and with excellent regio-, diastereo-, enantioselectivities under mild conditions without by-product formation. Representative large-scale reactions diverse transformations the products into various scaffolds potential biological activities render are also disclosed. mechanism was elucidated control DFT calculations.