Detailed experimental and computational studies have been carried out on the oxidative coupling of the alkenes C2 H3 Y (Y=CO2 Me (a), Ph (b), C(O)Me (c)) with 3-aryl-5-R-pyrazoles (R=Me (1 a), Ph (1 b), CF3 (1 c)) using a [Rh(MeCN)3 Cp*][PF6 ]2 /Cu(OAc)2 ⋅H2 O catalyst system. In the reaction of methyl acrylate with 1 a, up to five products (2 aa-6 aa) were formed, including the trans monovinyl...

Gel permeation chromatography (GPC), nuclear magnetic resonance (NMR) spectroscopy, and elemental analysis techniques were used to study the molecular characteristics of six commercially available styrene-butadiene-styrene (SBS) block copolymers which are mostly for modifying bitumen. The cis-1,4, trans-1,4, 1,2-vinyl units in polybutadiene (PB) parts styrene contents SBS investigated by means ...

The title compound, C(6)Cl(10), cystallizes in a nearly C2-symmetrical gauche conformation. Both trichloro-vinyl groups are nearly planar [Cl-C-C-Cl torsion angles = -178.47 (12) and -179.93 (11)°] and the lengths of their C-Cl bonds increase from the terminal trans and cis C-Cl bonds to the inter-nal bonds. The Cl-C-Cl bond angles of the terminal dichloro-methyl-ene units are compressed to 111...

The title compound, C9H7BrO2, displays a trans configuration with respect to the C=C double bond and is essentially planar [maximum deviation from the least-squares plane through all non-H atoms = 0.056 (4) Å]. The vinyl-aldehyde group adopts an extended conformation wih a C-C-C-C torsion angle of 179.7 (4)°. In the crystal, mol-ecules are linked by classical O-H⋯O and weak C-H⋯O hydrogen bonds...

Z. Naturforsch. 55 a, 481^185 (2000); received February 9, 2000 We have performed an investigation of the internal rotation of the methyl group in trans-cis ethyl vinyl ether by using molecular beam-Fourier transform Microwave (MB-FTMW) spectroscopy. Rotational spectra (up to J = 20) were recorded in the frequency region 4 -19 GHz. Due to the internal rotation of the methyl group, some rotation...

In the title compound, [Ir(C(11)H(6)F(2)N)(2)(C(22)H(17)N(4)O)]·CH(3)OH, the coordination at iridium is essentially octa-hedral, but with distortions associated with the bite angles of the ligands [76.25 (9)-80.71 (12)°] and the differing trans influences of C and N ligands [Ir-N = 2.04 Å (average) trans to N but 2.14 Å trans to C]. All three bidentate ligands have coordinating ring systems tha...

Herein we disclose the radical cation Diels–Alder reaction of aryl vinyl ethers by electrocatalysis, which is triggered by an oxidative SET process. The reaction clearly proceeds in a stepwise fashion, which is a rare mechanism in this class. We also found that two distinctive pathways, including “direct” and “indirect”, are possible to construct the Diels–Alder adduct. Introduction Umpolung, a...

poly vinyl alcohol/chitosan nanofibrous mat were prepared by electrospinning method with suitable pore sizes as potential matrices for soft tissue engineering. the designed scaffolds by electrospinning method evaluated by differentanalyses such morphological, mechanical, and cellular analysis.microscopic results showed diameters of poly vinyl alcohol/chitosan nanofibers were approximately 150 n...

in this research, a semi empirical approach has been suggested for calculating the activation energyof unimolecular thermal decomposition of vinyl ethers yielding saturated products. the calculationprocedure is based on the use of molecular mechanics (mm) methods. these methods which involvethe construction of the transition state for a molecule mainly consider the formation of a “hydrogenbridg...