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Aromatic para-functionalized NCN pincer compounds tethered to a triethoxysilane moiety through a carbamate linkage were immobilized on ordered MCM-41 molecular sieve using a grafting process. The acquired immobilized organometallic pincer complexes were synthesized in high yields with no complex degradation and characterized by IR sprctroscopy, elemental content analysis. Nitrogen physisorption, XRD and TEM revealed that the mesoporous structure was retained during the immobilization process. The hybrid materials were applied as Lewis acid catalysts in the α-arylation reaction between aryl ketones and aryl halides, with the yield up to 95%. The tendency to form mono- or di-arylated products was investigated and the catalyst could be easily recovered and reused in five runs without a significant loss in its activity.

A direct and efficient synthesis of arylketones via arylboronic acid addition to nitriles in presence of inexpensive Mn/Cu catalytic system is reported. The use of non-precious Mn and Cu salts has been found to be highly advantageous both in terms of accessibility as well as cost effectiveness. A series of arylboronic acids as well as nitriles were used to synthesize a variety of symmetrical and unsymmetrical arylketones. Based on the literature studies, the reaction mechanism is anticipated to go through an aryl radical intermediate which reacted with the copper activated nitrile to give the desired arylketones after the hydrolysis of the imine intermediate.

We report the catalytic alkylation of amide derivatives, which relies on the use of nonprecious metal catalysis. Amide derivatives are treated with organozinc reagents, utilizing nickel catalysis, to yield ketone products. The methodology is performed at ambient temperature and is tolerant of variation in both coupling partners. A precursor to a nanomolar glucagon receptor modulator was synthesized using the methodology, underscoring the mild nature of this chemistry and its potential utility in pharmaceutical synthesis. These studies are expected to further promote the use of amides as synthetic building blocks.

(R)-(+)-Trichostatic acid and (R)-(+)-trichostatin A (TSA) are natural products that have attracted considerable attention in the field of epigenetic therapies. TSA in particular is a naturally occurring hydroxamic acid having potent activity as a histone deacetylase inhibitor (HDACi) and having significant potential for treatment of a myriad of genetically based diseases. Development of TSA and other trichostatic acid derivatives into useful small-molecule therapies has been hindered by the low natural abundance and high cost associated with these compounds. We report herein our collective efforts towards the development of concise and scalable routes for the synthesis of trichostatic acid and TSA in both racemic and enantioenriched forms. Three independent synthetic pathways were developed with varying degrees of efficiency and convergency. In the first synthesis, the key step was a vinylogous Horner-Wadsworth-Emmons condensation. A Marshall propargylation reaction was used as the key step in the second synthesis, and Pd-catalyzed α-alkenylation of a ketone zinc enolate by using various functionalized alkenyl or dienyl halides was developed for the third synthesis. The second pathway proved to be readily amenable to an enantioselective modification, and both the second and third pathways were straightforwardly adapted for the facile preparation of new analogues of trichostatic acid and TSA. Three synthetic strategies have been developed for trichostatic acid and trichostatin A. Each strategy has a different key bond-forming step; a vinylogous Horner-Wadsworth-Emmons condensation, a Marshall propargylation, and coupling of a ketone enolate with various alkenyl halides. Two of the syntheses were efficient and able to produce analogues. Two of the syntheses were enantioselective. Copyright

Over a century ago, the first reactions of diazomethane with aldehydes delivered methyl ketones. In the interim, aldehydes have been homologated with trimethylsilyldiazomethane, diazoacetates, and aryldiazomethanes, on rare occasion with catalysis. This work describes a mild procedure for convergent ketone assembly from nonstabilized diazoalkanes, including examples of chiral ketone synthesis with disubstituted (internal) nucleophiles. The method's remarkable tolerance to steric crowding is showcased in a simple approach to achyrofuran, a complex dibenzofuran.

A novel series of 3-heteroaryl-5,6-bis(aryl)-1-methyl-2-pyridones were developed with high affinity for the benzodiazepine (BZ) binding site of human γ-aminobutyric acid (GABAA) receptor ion channels, low binding selectivity for α2- and/or α3- over α1-containing GABAA receptor subtypes and high binding selectivity over α5 subtypes. High affinity appeared to be associated with a coplanar conformation of the pyridone and sulfur-containing 3-heteroaryl rings resulting from an attractive S...O intramolecular interaction. Functional selectivity (i.e., selective efficacy) for α2 and/or α3 GABAA receptor subtypes over α1 was observed in several of these compounds in electrophysiological assays. Furthermore, an α3 subtype selective inverse agonist was proconvulsant and anxiogenic in rodents while an α2/α3 subtype selective partial agonist was anticonvulsant and anxiolytic, supporting the hypothesis that subtype selective BZ site agonists may provide new anxiolytic therapies.

Unsymmetrical aryl-benzyl or aryl-alkyl ketones are obtained by electrolysing in an undivided cell a DMF solution containing two organic halides, iron pentacarbonyl and a catalytic amount of a nickel-2,2′-bipyridine complex.

The photochemical reactions of crystal violet leuconitrile (CVCN) were investigated by the means of product analysis and trapping experiments, laser flash and steady-state photolysis, and steady-state fluorescence. The influence of oxygen on the reaction was examined in detail. The photochemistry of malachite green leuconitrile (MGCN), basic fuchsin leuconitrile (BFCN), and crystal violet leucomethyl (CVMe) and leucobenzyl (CVBn), as well as triphenylacetonitrile, was studied. The results suggest ionization occurs from S1, while the di-π-methane reaction is the photochemical route from T1.

The radical-cations of alkynylanilines are formed during the photolysis of ethynylanilines substituted at the para position in the presence of carbon tetrachloride and oxygen.They undergo two types of reaction, i.e. ejection of the alkyl substituent from

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