Direct β-C(sp(3))-H Functionalization of Aliphatic Amines to α,β-Unsaturated Imines, Aldehydes, and Chromenes
Sumana Mandal1, Sujit Mahato1, Chandan K Jana1
1Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.
Abstract:
A metal-free method for direct β-C(sp(3))-H functionalization of aliphatic amine was developed. The method is based on a reaction that yields enamine directly from the corresponding aliphatic amine, which otherwise requires the aid of metallic reagent and/or external oxidant. The reaction is operationally simple, general, and highly efficient in functionalizing both cyclic and acyclic amines. Structurally diverse unsaturated imines were obtained from N-heterocycles, while acyclic amines provided 2-alkyl cinnamaldehyde and benzopyran derivatives with excellent E/Z-selectivity.
Related Concept Videos
Preparation of Amines: Reductive Amination of Aldehydes and Ketones
Amines to Alkenes: Hofmann Elimination
Under thermal conditions, the hydroxide can abstract a proton from the β carbon; this generates an alkene with the simultaneous...
Amines to Amides: Acylation of Amines
Next, the second equivalent of amine serves as a Brønsted base and deprotonates the quaternary...
Preparation of 1° Amines: Gabriel Synthesis
Strong bases like NaOH or KOH deprotonate the phthalimide to form the corresponding anion, which acts as a nucleophile. Further, the anion attacks an...
Aldehydes and Ketones with Amines: Imine and Enamine Formation Overview
Nitriles to Amines: LiAlH4 Reduction
As shown below, the mechanism involves three steps. Firstly, the hydride ion acting as a nucleophile attacks the nitrile carbon to form an anion. In the second step, a second equivalent of the hydride ion attacks the anion to...


