Ligand‐free Iron(II)‐Catalyzed N‐Alkylation of Hindered Secondary Arylamines with Non‐activated Secondary and Primary Alcohols via a Carbocationic Pathway

Secondary benzylic alcohols represent a challenging class of substrates for N‐alkylation of amines. Herein, we describe an iron(II)‐catalyzed eco‐friendly protocol for N‐alkylation of secondary arylamines with secondary benzyl alcohols through a carbocationic pathway instead of the known borrowing hydrogen transfer (BHT) approach. Transiently generated carbocations, produced from alcohols via self‐condensation, were coupled with arylamines to provide highly functionalized amine products. The scope of this methodology involves N‐alkylation of primary, secondary and heterocyclic amines with primary/secondary benzylic, allylic and heterocyclic alcohols, which are common key structures in numerous pharmaceuticals drugs. The method can also be easily adopted for the amination of various natural products.