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Bi2O2Te is prepared by solid state reaction of a stoichiometric mixture of Bi, Bi2O3, and Te (evacuated silica tubes, 873 K, 10 h; complex heating schedule).

Published data on the chemistry of usnic acid since the time of its isolation in a pure state up to now are integrated and analyzed. The preparation methods, structure and properties of this compound are considered. The data on the chemical transformations of usnic acid comprise reactions that do not affect the carbon skeleton and reactions accompanied by carbon skeleton destruction. The bibliography includes 96 references.

A number of chalcones with the (+)- and (−)-usnic acid moieties were synthesized by the following sequence: the reaction of these acids with phenylhydrazine, reduction of the C(1)=O group with sodium borohydride, O-methylation of the intermediate compounds with diazomethane, and subsequent condensation with substituted benzaldehydes at the acetyl group.

The reaction proceeds regioselectively in the case of disubstituted anilines such as (VI) or β-naphthylamine (IV).

Many chemical reactions involve the electron transfer stage. The kinetics of photoinduced electron transfer reactions is commonly considered in terms of either the transition state theory as preliminary thermally activated reorganization of the medium and reactants (necessary for degeneracy of the electronic levels of the reactants and the products) or nonradiative quantum transitions, which do not require preliminary activation and are observed in the exoergic region. A new approach to the kinetics of such reactions that has been proposed recently considers a substantial reduction of the barrier in the contact reactant pair due to strong electronic interaction and takes into account the intermediate formation of a charge transfer complex. This approach has explained many well-known important features of electron transfer reactions that are inconsistent with the first two theories.

d-Glucose based homoallylic alcohol reacts smoothly with various aldehydes in the presence of arenes and a catalytic amount of BF3·OEt2 under mild conditions to afford a novel series of 5,7-diaryl-hexahydro-2H-furo[3,2-b]pyrans in good yields with high cis-selectivity.

Chemical vapor deposition (CVD) was used to deposit silver films for superconducting wire applications. AgI, silver trifluoroacetate (Ag(TFA)), and perfluoro-1-methylpropenylsilver (Ag(PF)) produced the most promising silver films. CVD processing was optimized on these three precursors using thermodynamic calculations performed using a modified version of the SOLGASMIX-PV computer program. Ag(PF) produced the highest quality silver films at low temperatures and pressures. A fiber tow which contained a silver barrier layer and a YBa2Cu3Ox overlayer was found to be a superconductor at 72 K.

C27H40O4, Mr = 428.6, orthorhombic, P2(1)2(1)2(1), a = 9.821(3), b = 25.766(6), c = 9.802(3) A, V = 2480(2) A3, Z = 4, Dx = 1.15 g cm-3, lambda(Mo K alpha) = 0.71073 A, mu = 0.70 cm-1, F(000) = 936, T = 295 K, final R = 0.063 for 2778 observed reflections. The A ring assumes a normal 1 alpha,2 beta-half-chair conformation. The progesterone side chain has a conformation typical of 17 alpha-ester steroids; the C(16)-C(17)-C(20)-O(20) torsion angle is -17.9(5) degrees.

Photoemission spectra of vacuum deposited layers of C 60 , before and after exposure to K vapor, show that the K donates its conduction electron into the band derived from the lowest unoccupied molecular orbital. A compound with composition of K 3 C 60 , corresponding to the maximum conductivity, has been prepared. In it the potassium atoms presumably occupy both the octahedral and the two tetrahedral interstitial sites of the face-centered-cubic (fcc) C 60 structure.

Chlorosulfonyl isocyanata (CSI) reacts with 2H-azirines 1 a-c at -78°C to form [2+2+2] cycloadducts 3a-c and 4a-c. The tricyclic aziridine derivatives 4a-c undergo CSI extrusion reactions and subsequent oxidation to the corresponding pyrazines 5a-c. Structural identifications of 3a-c and 4a-c are based on ir, nmr and mass spectral data.

The reaction of esters and amides of 3-phenyl-3-chloro-2-oxopropionic acid with thioamides and thiourea gave new 5-phenylthiazoles.

The reaction of chlorosulfonyl isocyanate with arylmethylenemalonaldehydes afforded the fused 1,3-oxazin-2-one derivatives.