摘要:
Methods of synthesizing compounds comprising fluorinated aryl groups are disclosed, wherein said methods utilize hydrogen bond directed photocatalytic hydrodefluorination.
摘要:
Disclosed is a method for producing oxygen (O 2 ) and hydrogen (H 2 ) from water, the method comprising (a) obtaining a composition comprising (i) a hybrid catalyst comprising an organo-iridium catalyst deposited on the surface of a titanium dioxide catalyst, and (ii) an aqueous solution having a buffer or having a base wherein the base is present in the aqueous solution in an amount at least 4 times equivalent with respect to the organo-iridium catalyst present on the hybrid catalyst, and (b) exposing the composition to light to produce O 2 and H 2 from water molecules in the aqueous solution.
摘要:
Synthetic methods are described herein operable to efficiently produce a wide variety of molecular species through conjugate additions via decarboxylative mechanisms. For example, methods of functionalization of peptide residues are described, including selective functionalization of peptide C-terminal residues. In one aspect, a method of peptide functionalization comprises providing a reaction mixture including a Michael acceptor and a peptide and coupling the Michael acceptor with the peptide via a mechanism including decarboxylation of a peptide reside.
摘要:
The present invention is directed to a process for preparing Substituted Indole Compounds of Formula (I): wherein R 1 , R 2 , R 3 and R 4 are as defined herein. These indole compounds are useful as synthetic intermediates for making inhibitors of HCV NS5A.
摘要:
Described herein is the fusion of two families of unique carbon-containing molecules that readily disregard the tendency of carbon to form four chemical bonds, namely N-heterocyclic carbenes (NHCs) and carborane anions. Deprotonation of an anionic imidazolium salt with lithium diisopropylamide at room temperature leads to a mixture of lithium complexes of C-2 and C-5 dianionic NHC constitutional isomers as well as a trianionic (C-2, C-5) adduct. Judicious choice of the base and reaction conditions allows for the selective formation of all three stable polyanionic carbenes. In solution, the so-called abnormal C-5 NHC lithium complex slowly isomerizes to the normal C-2 NHC, and the process can be proton catalyzed by the addition of the anionic imidazolium salt. These results indicate that the combination of two unusual forms of carbon atoms can lead to unexpected chemical behavior, and that this strategy paves the way for the development of a broad new generation of NHC ligands for catalysis.
摘要:
Disclosed herein are processes for dehydrogenation of an alkane to an alkene using an iridium pincer complex. In the dehydrogenation reactions, hydrogen that is co-formed during the process must be removed for the chemical reaction to proceed and to prevent the excess hydrogen from poisoning the catalyst. In one embodiment the process comprises providing an alkane feedstock comprising at least one alkane and contacting the alkane with an iridium pincer complex in the presence of a hydrogen acceptor selected from the group consisting of ethylene, propene, or mixtures to form an alkene product. The processes disclosed herein can accomplish facile, low-temperature transfer dehydrogenation of alkanes with unprecedented selectivities and TONs at a reasonable rate of conversion.
摘要:
Carbonylation catalysts and methods for using them are disclosed. In some embodiments, the carbonylation catalyst includes the contact product of: (a) a nitrogen compound selected from monomeric pyridines and imidazoles; (b) a Group VIII metal; and (c) an alkali metal compound; wherein the catalyst material is on a solid support.