Phosphoryl amidine synthesis using phosphoryl azides under the Cu-catalyzed three-component couplings

Abstract

Recently our group developed three-component coupling reaction of sulfonyl azide, alkyne and nucleophilic reaction partners such as amine, alcohol and water. We found that phosphoryl azide can also be used in this type of reaction affording corresponding amidines with good to excellent yields. Phosphoryl azide has more structural diversity than sulfonyl azides, to give more potential, practical application by changing the alcohol moiety. The introduction of BINOL (1,1’-Bi-2-naphthol), a typical chiral auxiliary into the amidine structure engendered an asymmetric environment on α-position of the amidine. This chiral amidine underwent successful asymmetric alkylation reactions with methyl, benzyl and allyl groups.