Generation of Coumarin‐3‐Carboxamides From Coumarin‐3‐Carboxylic Acids and Tetraalkylthiuram Disulfides Catalyzed by Copper Salts

Abstract

Amidation reactions of coumarin‐3‐carboxylic acids under mild conditions have been demonstrated in this work. Tetraalkylthiuram disulfides are utilized as the amidation reagents. This protocol is compatible with a variety of electron‐donating and electron‐withdrawing functional groups and provides an attractive strategy for the preparation of coumarin‐3‐carboxamides in moderate to good yields.

Piperidine-Iodine as Efficient Dual Catalyst for the One-Pot, Three-Component Synthesis of Coumarin-3-Carboxamides

“… General methods for the synthesis of coumarin-3-carboxamides: ( a ) Traditional approach multistep reactions [ 22 ], ( b ) MCRs using nanoparticles [ 24 , 25 ], ( c ) C-3 functionalization of coumarins [ 26 ], ( d ) amidation reaction [ 27 ], ( e ) MCRs using piperidine-iodine. …”

“…Alternatively, MCRs using magnetic nanoparticles (NPs) such as Ni–NiO and Fe 3 O 4 have also been applied in the synthesis of a variety of coumarin-3-carboxamides ( Figure 1 b) [ 24 , 25 ]. Other reported approaches to the synthesis of coumarin-3-carboxamide involve regioselective carboxamidation of coumarins at C-3 with formamides by using the radical initiator tert -butyl peroxybenzoate (TBPB) ( Figure 1 c) [ 26 ], and amidation reactions of coumarin-3-carboxylic acids using tetraalkylthiuram disulfides as amine sources ( Figure 1 d) [ 27 ].…”

Nickel-Catalyzed Amidation of Aryl Alkynyl Acids with Tetraalkylthiuram Disulfides: A Facile Synthesis of Aryl Alkynyl Amides

“… 12 Despite these advances, to the best of our knowledge, using thiuram reagents as amine sources to synthesize aryl alkynyl amides has not been precedented so far. As a continuation of this research program, 13 herein, we present a nickel-catalyzed amidation of aryl alkynyl acids with tetraalkylthiuram to synthesize aryl alkynyl amides ( Scheme 1 e).…”

Two Novel coumarin-based fluorescent probes for the detection of Cu2+ and biological applications

“…It is well known that the key element of probe design is the ability of an excellently chosen uorophore to combine with the detection group for speci c recognition. Coumarin dyes are widely used in uorescent probes because of their low biotoxicity, high uorescence sensitivity, good photostability and easy modi cation of the main chain [22][23][24][25][26][27][28][29][30] . Coumarin derivatives can also be used as uorescence markers or imaging agents to identify tumor lesions and study the subcellular localization of drugs [31][32][33][34][35][36][37][38][39][40][41][42] .…”