Amides are among the most fundamental functional groups and essential structural units, widely used in chemistry, biochemistry and material science. Amide synthesis and transformations is a topic of continuous interest in organic chemistry. However, direct catalytic asymmetric activation of amide C-N bonds still remains a long-standing challenge due to high stability of amide linkages. Herein, we describe an organocatalytic asymmetric amide C-N bonds cleavage of N-sulfonyl biaryl lactams under mild conditions, developing a general and practical method for atroposelective construction of axially chiral biaryl amino acids. A structurally diverse set of axially chiral biaryl amino acids are obtained in high yields with excellent enantioselectivities. Moreover, a variety of axially chiral unsymmetrical biaryl organocatalysts are efficiently constructed from the resulting axially chiral biaryl amino acids by our present strategy, and show competitive outcomes in asymmetric reactions.

A variety of γ-keto-β-silyl esters and amides, most with extremely high enantioselectivities, were efficiently prepared via a carbene-catalyzed formal [4 + 2] annulation followed by ring opening with nucleophiles. The resulting compounds from this one-pot strategy can be easily converted into enantioenriched β,σ-dihydroxyl esters.

Oxotryptamines were firstly used as flexible four-atom synthons in an NHC-catalyzed formal [4+ +3] annulation, providing an ovel enantioselective method to access structurally diverse spiro-e-lactam oxindoles with excellent enantioselectivities.T his metal-free reactionf eatures ab road substrate scope, excellent functional-group tolerance and proceeds under mild reaction conditions. Importantly,e nantiopure privileged hexahydropyrroloindoles could be easily constructed by ao ne-pot process from the resulting spiro-e-lactam oxindoles.Scheme1.Constructiono fseven-membered rings promoted by NHC.