silica-grafted n-propyl-diaza-15-crown-5 (sgpdc) with immobilized palladium nanoparticles was found as an efficient heterogeneous catalytic system for the heck and suzuki coupling reactions and satisfied results were obtained. different derivatives of aryl halides and alkenes under the heck reaction were converted to the corresponding products with good efficiency. the presence of electron-dona...

Title of Dissertation: DEVELOPMENT OF ARYL SILOXANE CROSSCOUPLING TECHNOLOGY AND ITS APPLICATION TO THE SYNTHESIS OF COLCHICINE AND ALLOCOLCHICINE DERIVATIVES William Michael Seganish, Doctor of Philosophy, 2005 Dissertation directed by: Professor Philip DeShong Department of Chemistry and Biochemistry One of the most versatile methods for the formation of aryl-aryl bonds is the palladium-catal...

The mechanism of the previously developed cross-coupling reaction of aryl Grignard reagents with aryl halides was explored in more detail. Single electron transfer from an aryl Grignard reagent to an aryl halide initiates a radical chain by giving an anion radical of the aryl halide. The following propagation cycle consists entirely of anion radical intermediates.

We report the Pd-catalyzed α-arylation of α,α-difluoroketones with aryl and heteroaryl bromides and chlorides catalyzed by an air- and moisture-stable palladacyclic complex containing P(t-Bu)Cy2 as ligand. The combination of this Pd-catalyzed arylation and base-induced cleavage of the acyl-aryl C-C bond within the α-aryl-α,α-difluoroketone constitutes a one-pot, two-step procedure to synthesize...

Human serum aryl acylamidase associated with serum cholinesterase was purified to homogeneity. Evidence for the identity of the two enzymes was based on co-elution profiles, co-purification in the different steps including affinity chromatography with constant ratios of specific activity and percentage recoveries, co-migration on gel electrophoresis, parallel inhibition by typical cholinesteras...

An investigation on the effect of substituent at the 2-position of mono-substituted quinoxalines in the synthesis of di-substituted quinoxaline derivatives via nucleophilic substitution reactions, is reported. Di-substituted quinoxalines bearing aryl-alky, aryl-aryl, aryl-heteroaryl, aryl-alkynyl, and amino-alkyl substituents were prepared in moderate to good yields. 2-Monosubstituted quinoxali...

The ruthenium(II)-catalyzed sp3 C-H bond arylation of benzylic amines with aryl halides is reported. In the present method, aryl iodides and, more importantly, also the cheaper aryl bromides and aryl chlorides can be applied as aryl sources. Additionally, the method does not require elaborate manipulations in a glove box and can be carried out in simple screw cap vials. Potassium pivalate prove...