Me<sub>3</sub>SI-promoted chemoselective deacetylation: a general and mild protocol
作者:Aakanksha Gurawa、Manoj Kumar、Sudhir Kashyap
DOI:10.1039/d1ra03209g
日期:——
Me3SI-mediated simple and efficient protocol for the chemoselective deprotection of acetyl groups has been developed via employing KMnO4 as an additive. This chemoselective deacetylation is amenable to a wide range of substrates, tolerating diverse and sensitive functional groups in carbohydrates, amino acids, natural products, heterocycles, and general scaffolds. The protocol is attractive because it uses
Silica-supported tantalum hydride activates at low temperature the CâH and the CâD bonds of cyclooctane and CD4, respectively, to form the corresponding cyclooctyl and perdeuteriomethyl-tantalum surface complexes; these complexes are transformed under molecular oxygen into the corresponding tantalum-alkoxy derivatives which with acetic acid give rise to the corresponding alkylacetates.
Concave reagents: Part 40—The copper(II) complex of a concave reagent as a selective catalyst for ester methanolysis
作者:Roberta Cacciapaglia、Stefano Di Stefano、Frank Fahrenkrug、Ulrich Lüning、Luigi Mandolini
DOI:10.1002/poc.735
日期:2004.4
We have shown that the CuII complexes of the concave ligand 1 and its model compound 2 are efficient catalysts of ester methanolysis under conditions close to neutrality. Turnover catalysis without product inhibition was demonstrated by the clean first-order release of a greater than stoichiometric amount of product. Compared with background methanolysis, the metal catalysts give greater rate accelerations
Gold-catalyzed oxidative cleavage of aryl-substituted alkynyl ethers using molecular oxygen. Simultaneous degradation of C–H and single and triple carbon–carbon bonds under ambient conditions
作者:Arindam Das、Rupsha Chaudhuri、Rai-Shung Liu
DOI:10.1039/b908338c
日期:——
We report the gold-catalyzed oxidativecleavage of aryl-substituted alkynyl ethers using molecular oxygen under ambient conditions; the transformation involves a remarkable cleavage of C-H, C-C and C[triple bond, length as m-dash]C bonds simultaneously.