Synthesis of benzo-ortho-thiazines S-oxides by Diels-Alder reaction of N-sulfinylanilines with norbornadiene

From substituted N-sulfinylanilines acting as dienes in the Diels-Alder reaction with norbornadiene S-oxides of benzo-ortho-thiazines were obtained, which were oxidized into the corresponding S,S-dioxides belonging to the class of hybrid thiazinesulfonamide compounds.     

It spectroscopic study of the interaction of chlorosilanes with the surface of aerosil

The surface-chemical reactions of the chlorosilanes

$$\left( {\begin{array}{*{20}c} {} & {} & {} & {{\text{CH}}_{\text{3}} } & {} & {} & {{\text{CH}}_{\text{3}} } & {} \\ {} & {} & {} & {} & {} & {} & {} & {} \\ {{\text{CL}}_{\text{3}} {\text{SiH,}}} & {{\text{CL}}_{\text{3}} {\text{Si}}} & {} & {} & {,{\text{ ClSi}}} & {} & {} & {\text{H}} \\ {} & {} & {} & {} & {} & {} & {} & {} \\ {} & {} & {} & {\text{H}} & {} & {} & {{\text{CH}}_{\text{3}} } & {} \\ {} & {} & {} & {} & {} & {} & {} & {} \\ \end{array} } \right)$$     

Products of the catalytic liquid-phase oxidation of 3-carene

The liquid-phase oxidation of 3-carene in the presence of various catalytic systems has been studied. The possibility has been shown of the directed preparation of 3-carene oxide, of ketones with a carane skeleton and a 7-membered ring, or of aromatic tertiary alcohols.Institute of Physical Organic Chemistry, Academy of Sciences of the Belorussian SSR, Minsk. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 328–334, May–June, 1991.     

Quantum-chemical study of the geometric and electronic structure of the chromate anion CrO 4 2− and a chromate group on the surface of finely divided silica by the CNDO/2 method

A comparative study of the geometric and electronic structure of the chromate anion CrO ₄ ^2– and a chromate group on the surface of finely divided silica (Si-O)₂-CrO₂, which was simulated by a CrO₉Si₆H₁₂ cluster, has been carried out by the SCF-MO-LCAO method in the all-valence-electron CNDO/2 approximation. The data obtained on the equilibrium geometry of the chromate group attest to the formation of a double bond between the Cr atom and each O atom (which is not bonded to Si). It has been shown that the support has a significant stabilizing influence on the energy of the MO's of the chromate group. The chromate group on an SiO₂ surface is characterized by partial delocalization of the frontier MO's among the skeletal bonds; however, the dominant contribution to the HOMO is made by the 2p AO of the oxygen atoms in the coordination shell of the Cr atom (70%), and the dominant contribution to the LUMO is made by the 3d AO of the chromium atom (50%). The positions and composition of the lowest unoccupied molecular orbitals point out the possibility of the display of electron-acceptor properties by a chromate group on an SiO₂ surface.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 24, No. 5, pp. 602–606, September–October, 1988.