Decarboxylative Umpolung Synthesis of Amines from Carbonyl Compounds

Abstract

2-Azaallyl anions are valuable intermediates which have versatile applications in functionalization with various electrophiles. Decarboxylation of the imines formed from aromatic aldehydes and α,α-diphenylglycine provides an interesting and efficient way to generate delocalized 2-azaallyl anions, which display high reactivity toward different electrophiles with excellent regioselectivity at the diphenylketimino aryl carbon of the 2-azaallyl anions. The transformation produces various amines in good yields under very mild conditions. This Synpacts article highlights the recent advances on the decarboxylative umpolung synthesis of amines from carbonyl compounds.1 Introduction2 Decarboxylative Umpolung Reactions of Carbonyl Compounds with Different Electrophiles2.1 Reaction with π-Allyl–Pd(II) Species2.2 Reaction with Morita–Baylis–Hillman Adducts2.3 Reaction with Imines2.3.1 Intermolecular Reaction with N-Ts Imines2.3.2 Intramolecular Reaction with Chiral N-tert-Butanesulfinyl Imines2.4 Reaction with Aldehydes and Ketones3 Decarboxylative Umpolung Reaction of α,β-Unsaturated Aldehydes with Aldehydes4 Conclusion