α,β-Differentiated tandem diamination of cinnamic esters using N,N-dichloro-2-nitrobenzenesulfonamide and acetonitrile as the nitrogen sources

Tandem diamination of cinnamic esters provides a new approach to anti alkyl Nα-(2-Ns), Nβ-Ac diaminophenylpropionates. The new reaction proceeds to completion within 3 hours at room temperature using N,N-dichloro-2-nitrobenzenesulfonamide (2-NsNCl2) as the nitrogen source in acetonitrile, which is also involved in the reaction process. Seven diamine derivatives have been obtained with good yields and stereoselectivity.