5493-38-9Relevant articles and documents
Amide bond formation in aqueous solution: Direct coupling of metal carboxylate salts with ammonium salts at room temperature
Nielsen, John,Tung, Truong Thanh
supporting information, p. 10073 - 10080 (2021/12/10)
Herein, we report a green, expeditious, and practically simple protocol for direct coupling of carboxylate salts and ammonium salts under ACN/H2O conditions at room temperature without the addition of tertiary amine bases. The water-soluble coupling reagent EDC·HCl is a key component in the reaction. The reaction runs smoothly with unsubstituted/substituted ammonium salts and provides a clean product without column chromatography. Our reaction tolerates both carboxylate (which are unstable in other forms) and amine salts (which are unstable/volatile when present in free form). We believe that the reported method could be used as an alternative and suitable method at the laboratory and industrial scales. This journal is
Metal-Free Selective Modification of Secondary Amides: Application in Late-Stage Diversification of Peptides
Adebomi, Victor,Sriram, Mahesh,Streety, Xavier,Raj, Monika
supporting information, p. 6189 - 6193 (2021/08/01)
Here we solve a long-standing challenge of the site-selective modification of secondary amides and present a simple two-step, metal-free approach to selectively modify a particular secondary amide in molecules containing multiple primary and secondary amides. Density functional theory (DFT) provides insight into the activation of C-N bonds. This study encompasses distinct chemical advances for late-stage modification of peptides thus harnessing the amides for the incorporation of various functional groups into natural and synthetic molecules.
Chemoselective Intramolecular Formal Insertion Reaction of Rh–Nitrenes into an Amide Bond Over C?H Insertion
Kono, Masato,Harada, Shingo,Nemoto, Tetsuhiro
supporting information, p. 3119 - 3124 (2019/02/13)
The past few decades have witnessed extensive efforts to disclose the unique reactivity of metal–nitrenes, because they could be a powerful synthetic tool for introducing the amine functionality into unactivated chemical bonds. The reactivity of metal–nitrenes, however, is currently mainly confined to aziridination (an insertion into a C=C bond) and C?H amination (an insertion into a C?H bond). Nitrene insertion into an amide C?N bond, however, has not been reported so far. In this work we have developed a rhodium-catalyzed one-nitrogen insertion into amide C?N and sulfonamide S?N bonds. Experimental and theoretical analyses based on density functional theory indicate that the formal amide insertion proceeds via a rhodium-coordinated ammonium ylide formed between the nitrene and the amide nitrogen, followed by acyl group transfer concomitant with C?N bond cleavage. Mechanistic studies have allowed rationalization of the origin of the chemoselectivity observed between the C?H and amide insertion reactions. The methodology presented herein is the first example of an insertion of nitrene into amide bonds and provides facile access to unique diazacyclic systems with an N?N bond linkage.