We observed the orientation of 4-trans-2-(pyrid-4-yl-vinyl)benzoic acid (PVBA) trimers on Pd(111) using scanning tunneling microscopy (STM) under ultrahigh vacuum (UHV). The image showed three different types of trimers, one of which does not follow predicted dimer orientations. This type of trimer displays 10° rotations of each molecule in clockwise or counterclockwise directions. Calculations...

Treatment of readily prepared (Z)-6-benzyloxy-1,1,1,2-tetrafluoro-6-methyl-2-hepten-4-yne with 1.5 equiv of LHMDS in -78 °C for 1 h gave the corresponding trifluoromethylated diyne in an excellent yield. This diyne was found to be a good substrate for the carbocupration with various higher-ordered cyanocuprates to give the corresponding vinylcuprates in a highly regio- and stereoselective manne...

The ordering of 4-[trans-2-(pyrid-4-yl-vinyl)] benzoic acid, a two-dimensional chiral species, was studied by scanning tunneling microscopy at noble metal surfaces. Homochiral molecules self-assemble in supramolecular chiral hydrogen-bonded twin chains, which order in nanogratings where the supramolecular chirality is strictly correlated over the entire microm domains without intimate molecular...

Aconityl-doxorubicin (ADOX) was synthesized by the modified method of Shen and Ryser. Two isomers of cis-ADOX (cis-configuration) and trans-ADOX (trans-configuration) were generated in the reaction of DOX and cis-aconitic anhydride. These products were separated completely by using HPLC and analyzed by TOF-MS spectroscopy and (1)H- and (13)C-NMR experiments. The yields of cis-ADOX and trans-ADO...

Bicyclodihydrosiloles were readily prepared from optically active enyne compounds by a radical cascade reaction triggered by tris(trimethylsilyl)silane ((Me3Si)3SiH). The reaction was initiated by the addition of a silyl radical to an α,β-unsaturated ester, forming an α-carbonyl radical that underwent radical cyclization to a terminal alkyne unit. The resulting vinyl radical attacked the silico...

The D0(2A?)–D1(2A?) electronic transition of resonance-stabilized radical C9H9 isomers cis- and trans-meta-vinylbenzyl (MVB) has been investigated using resonant two-color two-photon ionization (R2C2PI) laser-induced fluorescence. radicals were produced in a discharge m-vinyltoluene diluted Ar probed under jet-cooled conditions. origin bands the cis trans conformers are at 19 037 18 939 cm–1, r...

The thermal decomposition of 86 % vinyl chloride 14 % vinyl acetate copolymer wasstudied by the conductometry technique in the presence of nitrogen. The kinetics of stability andthermal degradation of vinyl chloride- co- vinyl acetate (PVC- co- PVAc) copolymer withcopper, copper oxide and tricalcium dicitrate (st) were investigated at various temperatures (150-180 oC ) in solution. The rate coe...

beside ziegler-natta and phillips catalysts the development of methylaluminoxane (mao) as cocatalyst incombination with metallocenes or other transition metal complexes for the polymerization of olefins haswidely increased the possibilities in controlling the polymer composition, polymer structure, tacticity and special properties with high precision. these catalysts allow the synthesis of isot...

nanocomposites based on vinyl ester resin (derakane 470-300) and nano clay (cloisite 30b) were prepared. the effect of clay content of 1, 3 and 5% (by weight) on the morphology, mechanical properties and water absorption of vinyl ester resin nanocomposites were studied. the nanocomposites were characterized  using  small-angle x-ray  scattering  (saxs),  feld  emission  scanning electron micros...