The fractional determination of triethyl lead, diethyl lead, inorganic lead and total lead in the urines of a patient with tetraethyl lead poisoning was performed by means of hydride generation-flameless atomic absorption spectrometry. The chemical species of lead in the urine 21 days after the exposure comprised about 50% diethyl lead, about 48% inorganic lead and about 2% triethyl lead. The f...

the reaction between trimethylamine with propargyl bromide was studied and the structure of triethyl propargyl ammonium bromide was illustrated by 1hnmr, ir, and mass spectra.

The synthesis and polymerizability of atom-bridged bicyclic monomers was surveyed. The monomers included lactams, ureas, urethanes, lactones, carbonates, ethers, acetals, orthoesters, and amines. Despite widely-varying structures, they almost all polymerized to give polymers with monocyclic rings in the chain. The polymerizations are grouped by mechanism: uncoordinated anionic, coordinated anio...

Synthesis and structural characterization of 1,4,2-oxazaphosphepines is described. The 1,4,2-oxazaphosphepines were obtained from reaction of chiral 1,3-benzoxazines with dichlorophenylphosphine or triethyl phosphite. The configuration of some of these compounds was stablished by X-ray analysis.

To understand the molecular interactions between N,N-dimethylformamide with two families of ionic liquids, the thermophysical properties such as densities and ultrasonic sound speeds have been measured over the entire composition range at 25 C under atmospheric pressure. The materials investigated in the present study include two families of ionic liquids, viz., ammonium salts and imidazolium s...

Palladium(II) catalyzed carbonylation of 1-ethynyl-1-propargyl acetate is described; in the absence of the bisoxazoline (box) ligand, the second triple bond did not react, affording cyclic orthoesters and . The use of meso-Phbox-Pd(ii) strikingly changed the course of the reaction, yielding bicyclic lactone by tandem carbonylative cyclization as a result of insertion of the second triple bond.

The first stereoselective version of an iodine(III)-mediated rearrangement of arylketones in the presence of orthoesters is described. The reaction products, α-arylated esters, are very useful intermediates in the synthesis of bioactive compounds such as ibuprofen. With chiral lactic acid-based iodine(III) reagents product selectivities of up to 73 % ee have been achieved.

Selective activation of propargyl 1,2-orthoesters in the presence of propargyl glycosides and propargyl ethers was studied; a catalytic amount of AuBr3 activated the propargyloxy group of the 1,2-orthoester thereby giving access to disaccharides with the propargyl group at the reducing end; furthermore, propargyl ethers were unaffected under the reaction conditions.

The Johnson-Claisen rearrangement of D-gluco and L-ido-derived allylic orthoesters afforded gamma,delta-unsaturated ester that on ester reduction, epoxidation, regioselective oxirane opening by sodium azide and hydrogenation led to sugar amino alcohols--immediate precursors for 1-deoxy-homonojirimycin 3a,b, and polyhydroxylated homoazepanes 4a,b. Our synthetic approach and glycosidase inhibitor...