160150-35-6Relevant academic research and scientific papers
Decarboxylative palladium(II)-catalyzed synthesis of aryl amidines from aryl carboxylic acids: Development and mechanistic investigation
Rydfjord, Jonas,Svensson, Fredrik,Trejos, Alejandro,Sjoeberg, Per J. R.,Skoeld, Christian,Saevmarker, Jonas,Odell, Luke R.,Larhed, Mats
supporting information, p. 13803 - 13810 (2013/10/22)
A fast and convenient synthesis of aryl amidines starting from carboxylic acids and cyanamides is reported. The reaction was achieved by palladium(II)-catalysis in a one-step microwave protocol using [Pd(O 2CCF3)2], 6-methyl-2,2'-bipyridyl and trifluoroacetic acid (TFA) in N-methylpyrrolidinone (NMP), providing the corresponding aryl amidines in moderate to excellent yields. The protocol is very robust with regards to the cyanamide coupling partner but requires electron-rich ortho-substituted aryl carboxylic acids. Mechanistic insight was provided by a DFT investigation and direct ESI-MS studies of the reaction. The results of the DFT study correlated well with the experimental findings and, together with the ESI-MS study, support the suggested mechanism. Furthermore, a scale-out (scale-up) was performed with a non-resonant microwave continuous-flow system, achieving a maximum throughput of 11 mmol h-1 by using a glass reactor with an inner diameter of 3 mm at a flow rate of 1 mL min -1. Aryl amidines with ease: A PdII-catalyzed decarboxylative synthesis of aryl amidines from aryl carboxylic acids and cyanamides was developed and investigated with the aid of ESI-MS studies and DFT calculations (see scheme).
5-acylamino-1,2,4-thiadiazoles, their preparation and pharmaceutical compositions containing them
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, (2008/06/13)
The invention relates to thiadiazole derivatives corresponding to the general formula STR1 in which Ar represents a nitrogen-containing aromatic heterocycle, in particular indolyl which is substituted or unsubstituted on the nitrogen atom with CO--(C
