774-65-2Relevant articles and documents
Silver(I)-carbene complexes/ionic liquids: Novel N-heterocyclic carbene delivery agents for organocatalytic transformations
Sentman, Alan C.,Csihony, Szilard,Waymouth, Robert M.,Hedrick, James L.
, p. 2391 - 2393 (2005)
(Chemical Equation Presented) N-Heterocyclic carbene (NHC) complexes with silver were investigated as sources of unsaturated NHC carbene catalysts via thermal decomposition. The NHC complex (1-ethyl-3-methylimidazol-2-ylidene) silver(I) chloride is an ionic liquid, and was found to catalyze the ring-opening polymerization of lactide at elevated temperatures to give narrowly dispersed polylactide of predictable molecular weight. Silver-carbene complexes can also be used for the catalysis of small molecule transesterification reactions. Thermolysis of the silver complexes in the presence of CS2 yielded the zwitter-ionic CS2 adducts of the carbene, implicating the intermediacy of the free carbene in these reactions.
Synthesis, characterization, and catalytic properties of SiPW-X mesoporous silica with heteropolyacid encapsulated into their framework
Shi, Chunfeng,Wang, Runwei,Zhu, Guangshan,Qiu, Shilun,Long, Jun
, p. 4801 - 4807 (2005)
A series of SiPW-X mesoporous silica with Keggin-type heteropolyacids (HPAs) encapsulated into their framework have been synthesized under strong acidic conditions. During hydrolysis of tetraethyl orthosilicate (TEOS), Na 2HPO4 (P source) and Na2WO4 (W Source) are added into the initial sol-gel system to form Keggin type HPAs. The final products have been intensively characterized by various techniques, such as XRD, TEM, N2 adsorption isotherm analysis, and by IR, UV/Visible, and 31P Magic Angle Spinning (MAS) NMR spectroscopy. Characterization results suggest that samples with an HPA weight percent of 13.3-20.7 % show very ordered hexagonal mesostructures. In addition, HPAs incorporated in the mesosilica are insoluble during catalysis. Results of catalytic tests show that SiPW-X materials have catalytic activities that are comparable to bulk HPA in catalytic tests implementing chemical reactions of both small (cumene cracking and esterification of ethanol with acetic acid) and bulky (1,3,5- triisopropylbenzene cracking and esterification of benzoic acid with tert-butanol) molecules. It can be readily separated from the reaction system for reuse, which suggests the potential industrial application. Wiley-VCH Verlag GmbH & Co. KGaA, 2005.
Direct Amidation of Esters by Ball Milling**
Barreteau, Fabien,Battilocchio, Claudio,Browne, Duncan L.,Godineau, Edouard,Leitch, Jamie A.,Nicholson, William I.,Payne, Riley,Priestley, Ian
supporting information, p. 21868 - 21874 (2021/09/02)
The direct mechanochemical amidation of esters by ball milling is described. The operationally simple procedure requires an ester, an amine, and substoichiometric KOtBu and was used to prepare a large and diverse library of 78 amide structures with modest to excellent efficiency. Heteroaromatic and heterocyclic components are specifically shown to be amenable to this mechanochemical protocol. This direct synthesis platform has been applied to the synthesis of active pharmaceutical ingredients (APIs) and agrochemicals as well as the gram-scale synthesis of an active pharmaceutical, all in the absence of a reaction solvent.
N-Aroylbenzotriazoles as Efficient Reagents for o-Aroylation in Absence of Organic Solvent
Hahnvajanawong, Viwat,Phungpis, Baramee
, p. 2671 - 2674 (2021/10/25)
N-Aroylbenzotriazoles have been shown to be efficient reagents for esterification in the absence of organic solvent. Grinding of N-aroylbenzoytiazoles with twofold excess of alcohols for a couple of hours at room temperature gave corresponding esters in high percentage of yields.
