820232-28-8Relevant academic research and scientific papers
PROCESS FOR PRODUCING 3-ACYLAMINOBENZOFURAN-2-CARBOXYLIC ACID DERIVATIVE
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Page/Page column 25, (2008/06/13)
The present invention provides a process of preparing a compound of the formula [I]: wherein X is a group of the formula: -N="or" -CH=; R1 is a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group, a cyano group or an amino group optionally substituted by a lower alkyl group; Ring A is a nitrogen-containing heterocyclic group; Ring B is an optionally substituted benzene ring or an optionally substituted pyridine ring; and R3 is a hydrogen atom or a lower alkyl group, or a pharmaceutically acceptable salt thereof , which is useful as an inhibitor of activated blood coagulation factor X.
A practical synthesis of highly functionalized aryl nitriles through cyanation of aryl bromides employing heterogeneous Pd/C
Hatsuda, Masanori,Seki, Masahiko
, p. 1849 - 1853 (2007/10/03)
An industrially viable cyanation of aryl bromides with Zn(CN)2 was accomplished in the presence of inexpensive and readily accessible Pd/C, Zn dust, ZnBr2, and PPh3 in DMA to provide functionalized aryl nitriles in moderate to high yields.
A practical synthesis of highly functionalized aryl nitriles through cyanation of aryl bromides employing heterogeneous Pd/C: In quest of an industrially viable process
Hatsuda, Masanori,Seki, Masahiko
, p. 9908 - 9917 (2007/10/03)
Preparation of aryl nitrile 2a through classical Rosenmund-von Braun reaction of aryl bromide 1a resulted in a poor yield (61%) due to a high reaction temperature (165°C) and a lack of efficient procedure for separating 2a from a large quantity of heavy metal waste (Cu salts). To address these issues, a practical synthesis of multifunctional aryl nitriles through cyanation of aryl bromides has been developed with heterogeneous Pd/C used as the catalyst. Treatment of aryl bromides 1 with Zn(CN)2 in the presence of Pd/C, Zn, ZnBr2 and PPh3 in DMA provided aryl nitriles 2 involving those carrying sterically demanding electron-rich substituent in good yields and in highly reproducible manner. The activity of Pd/C is highly dependent on the properties of the Pd/C. Oxidic thickshell type catalyst Pd/C D5 was found to furnish the highest rate acceleration and yield. The use of heterogeneous Pd/C might anchor and disperse Pd over the solid support of the catalyst, at least in the initial stage of the reaction, to assure the formation of monomeric Pd complex without precipitating to inactive Pd black. The use of a slightly excess of Zn(CN)2 (0.6 equiv) and air oxidation of phosphine ligand, after end of the reaction, converted Pd species to insoluble phosphine-free Pd cyanides, from which Pd was recovered in high yield through simple filtration followed by usual recovery process involving combustion.
