Regioand stereoselective photoallylation of electron-deficient alkenes by use of allylic silanes via photoinduced electron transfer has been described. Similar photoinduced functionalization reactions such as arylmethylation, alkylation, and silylation can be achieved by using a variety of organosilicon compounds. These photoreactions proceed via radical cations of organosilicon compounds and r...

4-amino-1-(beta-D-ribofuranosyl)quinazolin-2-one (3) was prepared by a direct glycosylation of 4-aminoquinazolin-2-one (7) using the Vorbruggen's silylation method and provided exclusively the beta-anomer. This quinazoline nucleoside and its 2',3'-O-isopropylidene derivative (9) did not undergo the coupling reaction with dialkyl disulfides in the presence of tri-n-butylphosphine unless their 4-...

A new method for the intramolecular glycosylation of alcohols is described. Utilizing carbohydrate-derived silanes, the catalytic dehydrogenative silylation of alcohols is followed by intramolecular glycosylation. Appropriate combinations of silane position and protecting groups allow highly selective access to bmanno, a-gluco, or b-gluco stereochemical relationships as well as 2-azido-2-deoxy-...

Regioselective C-H functionalization of arenes has widespread applications in synthetic chemistry. The regioselectivity of these reactions is often controlled by directing groups or steric hindrance ortho to a potential reaction site. Here, we report a catalytic intermolecular C-H silylation of unactivated arenes that manifests very high regioselectivity through steric effects of substituents m...

C CP MAS NMR and Si MAS NMR were used to characterize silylated montmorillonites and to estimate the extent of the silylation reaction. Indirectly-detected proton relaxation times of the intercalated surfactant were measured in both silylated and non-silylated clay systems to monitor the dynamics of intercalated species. A greater degree of mobility in the silylated montmorillonites was found. ...

We describe an efficient photoredox system, relying on decatungstate/disulfide catalysts, for the hydrofunctionalization of styrenes. In this methodology use disulfide as a cocatalyst was shown to be crucial reaction efficiency. This system employed hydro-carbamoylation, -acylation, -alkylation, and -silylation styrenes, giving access large variety useful building blocks high-value molecules su...

The title compound, C20H47NO6Si4, was synthesized by per-O-tri-methyl-silylation of N-acetyl-d-glucosa-mine using chloro-tri-methyl-silane in the presence of hexa-methyl-disiloxane. The tri-methyl-silyl group and acetamido group are located on the same side of the pyran ring, showing an α-configuration glycoside. One of the tri-methyl-silyl groups is disordered over two orientations, with site-...

Electrochemical reduction of complexes of monochlorosilanes with redox-active ligands such as 2,2'-bipy occurs in one-electron fashion at moderately negative potentials, E @ -1 V vs SCE (in CH3CN/0.1 M Bu4NBF4), leading to silyl radicals. These radicals, trapped with a-phenyl-N-tbutyl-nitrone and characterized as spin-adducts by ESR spectroscopy, add to carbon interfaces (glassy carbon, graphit...

A novel procedure is described for the derivatization of fatty acid epoxides in the presence of their corresponding diols. The acidic character of 2,3,5,6-tetrafluorobenzenethiol promotes favorable mass fragmentation of linoleate and arachidonate derived epoxide derivatives and reduces alkene isomerization to a manageable side reaction, eliminated through the addition of a thiol scavenger. Afte...