6063-50-9Relevant articles and documents
Dichloromeldrum's acid (DiCMA): A practical and green amine dichloroacetylation reagent
Heard, David M.,Lennox, Alastair J.J.
supporting information, p. 3368 - 3372 (2021/05/06)
Dichloromeldrum's acid is introduced as a bench-stable, nonvolatile reagent for the dichloroacetylation of anilines and alkyl amines to produce α,α-dichloroacetamides, which are important motifs for medicinal chemistry. Products are formed in good to excellent yields with reagent grade solvents, and, as the only byproducts are acetone and CO2, no column chromatography is required. Thus, this reagent is practical, efficient, and green for the dichloroacetylation of primary amines.
Hafnium-catalyzed direct amide formation at room temperature
Lundberg, Helena,Adolfsson, Hans
, p. 3271 - 3277 (2015/06/16)
Herein, the first example of a metal-catalyzed protocol for direct amidation of nonactivated carboxylic acids at ambient temperature (26 °C) is presented. The mild reaction conditions give rise to high yields of a range of amides in reaction times as short as 90 min, employing a commercial hafnium complex, [Hf(Cp)2Cl2], as catalyst. Amino acids are transformed into their corresponding amides without racemization, and the catalyst displays full selectivity for the amidation of carboxylic acids over esters. Electronic properties of the carboxylic acids were found to have a strong influence on the rate of the amidation reaction, and the need for a balanced amount of molecular sieves was observed to be highly important for optimal reaction outcome.
Direct amide coupling of non-activated carboxylic acids and amines catalysed by zirconium(IV) chloride
Lundberg, Helena,Tinnis, Fredrik,Adolfsson, Hans
supporting information; experimental part, p. 3822 - 3826 (2012/05/20)
Amidst the green: A green, mild and effective protocol for the direct formation of secondary and tertiary amides from non-activated carboxylic acids and amines in good to excellent yields by employing ZrCl4 as the catalyst is presented (see scheme). The amide coupling protocol proved to be suitable for scaled up syntheses, and the mild reaction conditions conserve the enantiopurity of chiral starting materials. Copyright