13205-46-4Relevant articles and documents
Polymer-Supported Mitsunobu Ether Formation and its Use in Combinatorial Chemistry
Krchnak, Viktor,Flegelova, Zuzka,Weichsel, Aleksandra S.,Lebl, Michal
, p. 6193 - 6196 (1995)
Aromatic hydroxy acids have been attached to a polymeric solid support and the phenolic hydroxy groups have been reacted with a variety of primary and secondary alcohols under the conditions of the Mitsunobu reaction (triphenylphosphine and diethyl azodicarboxylate) in tetrahydrofuran.In most cases the reaction provided a nearly quantitative yield of alkyl aryl ethers, as determined after cleaving theproduct from the resin.To demonstrate that the polymer-supported Mitsunobu reaction is useful for combinatorial library synthesis, we synthesized a number of model compounds and a simple three randomization step library composed of 4,200 different compounds.
Cleavage of Carboxylic Esters by Aluminum and Iodine
Sang, Dayong,Yue, Huaxin,Fu, Yang,Tian, Juan
, p. 4254 - 4261 (2021/03/09)
A one-pot procedure for deprotecting carboxylic esters under nonhydrolytic conditions is described. Typical alkyl carboxylates are readily deblocked to the carboxylic acids by the action of aluminum powder and iodine in anhydrous acetonitrile. Cleavage of lactones affords the corresponding ω-iodoalkylcarboxylic acids. Aryl acetylates undergo deacetylation with the participation of the neighboring group. This method enables the selective cleavage of alkyl carboxylic esters in the presence of aryl esters.
Soluble/MOF-Supported Palladium Single Atoms Catalyze the Ligand-, Additive-, and Solvent-Free Aerobic Oxidation of Benzyl Alcohols to Benzoic Acids
Tiburcio, Estefanía,Greco, Rossella,Mon, Marta,Ballesteros-Soberanas, Jordi,Ferrando-Soria, Jesús,López-Haro, Miguel,Hernández-Garrido, Juan Carlos,Oliver-Meseguer, Judit,Marini, Carlo,Boronat, Mercedes,Armentano, Donatella,Leyva-Pérez, Antonio,Pardo, Emilio
, p. 2581 - 2592 (2021/02/16)
Metal single-atom catalysts (SACs) promise great rewards in terms of metal atom efficiency. However, the requirement of particular conditions and supports for their synthesis, together with the need of solvents and additives for catalytic implementation, often precludes their use under industrially viable conditions. Here, we show that palladium single atoms are spontaneously formed after dissolving tiny amounts of palladium salts in neat benzyl alcohols, to catalyze their direct aerobic oxidation to benzoic acids without ligands, additives, or solvents. With this result in hand, the gram-scale preparation and stabilization of Pd SACs within the functional channels of a novel methyl-cysteine-based metal-organic framework (MOF) was accomplished, to give a robust and crystalline solid catalyst fully characterized with the help of single-crystal X-ray diffraction (SCXRD). These results illustrate the advantages of metal speciation in ligand-free homogeneous organic reactions and the translation into solid catalysts for potential industrial implementation.