A Practical Approach for the Transamidation of N,N-Dimethyl Amides with Primary Amines Promoted by Sodium tert-Butoxide under Solvent-Free Conditions

A practical sodium tert-butoxide (NaOtBu)-mediated protocol is disclosed for the transamidation of various N,N-dimethyl amides with primary amines to afford the corresponding amides in moderate to good yields at room temperature under solvent-free conditions. This protocol features a facile work-up procedure and good functional group compatibility, especially for N,N-dimethyl amides with long-chain alkyl groups and heteroatom-containing amines. Notably, a few representative gram-scale reactions proceed smoothly to furnish the desired amides in high yields, which demonstrates the potential of this process for further practical applications. Several control experiments are carried out and a plausible mechanism is provided.

[1]  L. Cavallo,et al.  Buchwald–Hartwig cross-coupling of amides (transamidation) by selective N–C(O) cleavage mediated by air- and moisture-stable [Pd(NHC)(allyl)Cl] precatalysts: catalyst evaluation and mechanism , 2020, Catalysis Science & Technology.

[2]  S. Jana,et al.  KOtBu-Promoted Transition-Metal-Free Transamidation of Primary and Tertiary Amides with Amines. , 2019, Organic letters.

[3]  Chuanming Yu,et al.  Potassium tert -Butoxide Prompted Highly Efficient Transamidation and Its Coordination Radical Mechanism , 2019, European Journal of Organic Chemistry.

[4]  S. Nolan,et al.  [Pd(NHC)(acac)Cl]: Well-Defined, Air-Stable, and Readily Available Precatalysts for Suzuki and Buchwald-Hartwig Cross-coupling (Transamidation) of Amides and Esters by N-C/O-C Activation. , 2019, Organic letters.

[5]  Théo P. Gonçalves,et al.  Diverse catalytic reactivity of a dearomatized PN3P*-nickel hydride pincer complex towards CO2 reduction. , 2018, Chemical communications.

[6]  P. Brennan,et al.  Mild, calcium catalysed Beckmann rearrangements. , 2018, Chemical communications.

[7]  Q. Guo,et al.  An Efficient Heterobimetallic Lanthanide Alkoxide Catalyst for Transamidation of Amides under Solvent‐Free Conditions , 2017 .

[8]  T. Langer,et al.  Chemoselective Schwartz Reagent Mediated Reduction of Isocyanates to Formamides. , 2016, Organic letters.

[9]  P. Dyson,et al.  Thiazolium carbene catalysts for the fixation of CO2 onto amines. , 2016, Chemical communications.

[10]  M. Salamone,et al.  Kinetic solvent effects on the reactions of the cumyloxyl radical with tertiary amides. Control over the hydrogen atom transfer reactivity and selectivity through solvent polarity and hydrogen bonding. , 2015, The Journal of organic chemistry.

[11]  E. Doris,et al.  Carbon Nanotube–Gold Nanohybrid Catalyzed N‐Formylation of Amines by using Aqueous Formaldehyde , 2014 .

[12]  L. Becerra-Figueroa,et al.  Transamidation of carboxamides catalyzed by Fe(III) and water. , 2014, The Journal of organic chemistry.

[13]  Chengchao Li,et al.  Mesoporous Niobium Oxide Spheres as an Effective Catalyst for the Transamidation of Primary Amides with Amines , 2014 .

[14]  H. Neumann,et al.  Efficient copper(II)-catalyzed transamidation of non-activated primary carboxamides and ureas with amines. , 2012, Angewandte Chemie.

[15]  K. Shimizu,et al.  Transamidation of amides with amines under solvent-free conditions using a CeO2 catalyst , 2012 .

[16]  H. Sharghi,et al.  ZnO as a new catalyst for N-formylation of amines under solvent-free conditions. , 2006, The Journal of organic chemistry.

[17]  M. Shi,et al.  Transamidation Catalyzed by a Recoverable and Reusable PolyDMAP‐Based Hafnium Chloride and Montmorillonite KSF , 2005 .

[18]  J. Legros,et al.  DMF as a dimethylamine equivalent in the palladium-catalyzed nucleophilic substitution of naphthylmethyl and allyl acetates , 1997 .

[19]  C. Rao,et al.  Crystal and molecular structures of alkali- and alkaline-earth-metal complexes of N,N-dimethylformamide , 1984 .