6063-50-9Relevant academic research and scientific papers
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.
Direct amidation of non-activated carboxylic acid and amine derivatives catalyzed by TiCp2Cl2
Wang, Hui,Dong, Wei,Hou, Zhipeng,Cheng, Lidan,Li, Xiufen,Huang, Longjiang
, (2020/02/15)
This paper described a mild and efficient direct amidation of non-activated carboxylic acid and amine derivatives catalyzed by TiCp2Cl2. Arylacetic acid derivatives reacted with different amines to afford the corresponding amides in good to excellent yield except of aniline. Aryl formic acids failed to react with aniline but smoothly reacted with aliphatic amines and benzylamine in moderate to good yield, fatty acids reacting with benzyl and aliphatic amines give amides in good to excellent yield. Chiral amino acids derivatives were transformed into amides without racemization in moderate yield. The possible mechanism of direct amidation catalyzed by TiCp2Cl2 was discussed. This catalytic method is very suitable for the amidation of low sterically hindered arylacetic acid, fatty acids with different low sterically hindered amines except aniline, as well as the amidation of aryl formic acid with benzyl and aliphatic 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
Titanium(IV) isopropoxide as an efficient catalyst for direct amidation of nonactivated carboxylic acids
Lundberg, Helena,Tinnis, Fredrik,Adolfsson, Hans
supporting information, p. 2201 - 2204 (2012/10/30)
Secondary and tertiary amides are formed in high yields, in an efficient and environmentally benign titanium(IV) isopropoxide catalyzed direct amidation of carboxylic acids with primary and secondary amines. Georg Thieme Verlag Stuttgart ? New York.
One-pot conversion of t-butyl carbamates to amides with acyl halide-methanol mixtures
Nazih, Abdesslame,Heissler, Denis
, p. 203 - 206 (2007/10/03)
Acyl halide-methanol mixtures are efficient reagents for the one-pot transformation of t-butyl carbamates into amides. This transformation can be carried out in the presence of a benzyloxycarbonyl group.
