A theoretical study of the kinetics and mechanism of second-order intermolecular C.) cloadd it ion of 2-Ethyny1-2,3-Dihydrofurane and Phenyl Azide was performed using DFT method at 101.111 le) cl of theory with 6-31 PrEG(d,p) basis set at 298.15K. Equilibrium molecular geometries and harmonic ) ihrational frequencies ofthe reactants, transition state, and product were calculated. The kinetic an...

We first found experimentally a cycloaddition reaction of a molecule on a symmetry Si pair, 1,3-butadiene on the Si adatom pair of Si(111)7x7, while up to now only asymmetric Si pairs were reported to be involved in cycloaddition reactions on Si surfaces. As the symmetry of a Si pair is expected to influence significantly a cycloaddition product and a reaction pathway, the [4+2]-like cycloaddit...

Received September 21, 2011; accepted March 19, 2012. From the New York–Presbyterian Hospital, Columbia University Medical Center and Cardiovascular Research Foundation, New York, NY (G.F.R., A.J.K., P.G., A.J.L., E.C., G.W., H.P., M.F., R.M., G.W.S.), and Mayo Clinic, Rochester, MN (B.J.G.). Correspondence to Gregg W. Stone, MD, Columbia University Medical Center, Cardiovascular Research Found...

optimized HYPR-LR 7 8 John M. Floberg 9 Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, 10 Madison, WI 53705 11 12 Charles A. Mistretta and Jamey P. Weichert 13 Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, 14 Madison, WI 53705 and Department of Radiology, University of Wisconsin-Madison, 600 15 Highland Avenue, Madis...

2-Aminodienes, in which the enamine function is incorporated in a five-, six-, or seven-membered ring, react with dimethyl acetylenedicarboxylate in a sequence of [2+2] cycloaddition and electrocyclic ring-opening to form the two-carbon ring expanded unsaturated heterocycles, i.e., 3,4dicarboxylate substituted 6,7-dihydro-1H-azepines 3, 8 and 21, 1,6,7,8-tetrahydroazocines 22, and 6,7,8,9-tetra...

We have used photo-crosslinking to investigate the structure and dynamics of four-way junction hairpin ribozyme constructs. Four phenylazide photo-crosslinkers were coupled to 2'-NH2-modified U+2 in the substrate and irradiated at different Mg2+ concentrations and temperatures. Consistent with the role of divalent metal ions in hairpin ribozyme folding, we observed more interdomain crosslinks i...

A microwave-assisted synthesis of 2-(4-((1-phenyl-1H-1,2,3-triazol-4-yl)methoxy)phenyl)-1H-benzo[d]imidazoles from a phenylazide, propargyloxybenzaldehyde and a 1,2-diaminobenzene is proposed.

The photochemistry and molecular structure of 1-phenyl-4-allyl-tetrazolone (PAT) was studied by FT-IR matrix isolation spectroscopy and DFT(B3LYP)/6-311++G(d,p) calculations. The spectrum of matrix-isolated PAT monomers agrees well with the sum spectrum of three conformers predicted theoretically. UV irradiation (lambda > 235 nm) of matrix-isolated PAT induces three types of photofragmentation:...

A family of polymer-attached phenanthrolines was prepared from solvothermal copolymerization of divinylbenzene with N-(1,10-phenanthroline-5-yl)acrylamide in different ratios. The polymer-supported copper catalysts were obtained through typical impregnation with copper(II) salts. The polymers and supported copper catalysts have been characterized by N2 adsortion, scanning electron microscopy (S...