Autooxidation of 2-isobutyl-5,6-benzo-1,3,2-dioxaborepane

Using PMR, IR, and mass spectrometric methods it was shown that the main autooxidation product upon prolonged storage of 2-isobutyl-5,6-benzo-1,3,2-dioxaborepane is 2,2′-oxybis(5,6-benzo-1,3,2-doxaborepane). A. V. Bogatskii Physicochemical Institute, National Academy of Sciences of Ukraine, Odessa 270080. Organic Chemistry Institute, Ufa Science Center, Russian Academy of Sciences, Ufa 450054. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1418–1421, October, 1998.     

Reaction of 2-Isopropyl-5,6-benzo-1,3,2-oxazaborepane with Acetonitrile

Russian Journal of General Chemistry -     

Synthesis and certain properties of 2-substituted 4,5-benzo-1,3,2-thiazaphospholanes

Conclusions In the reaction of o-aminothiophenol and N-methyl-o-aminothiophenol with tetraalkyldiamidophosphites and phosphonites, 2-substituted 4,5-benzo-1,3,2-thiazaphospholanes were obtained in high yields. On heating, 2-alkyl-4,5-benzo-1,3,2-thiazaphospholanes can transform into spirophosphoranes with a P-C bond.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1108–1113, May, 1981.     

Molecular and crystal structure of 2-phenyl-2-oxo-5,6 -benzo-1,3,2-dioxaphosphepine

The seven-membered heterocycle in the crystal structure of 2-phenyl-2-oxo-5,6-benzo-1,3,2-dioxaphosphepine has distorted (asymmetric) twist conformation and the plane of the phenyl substituent at the phosphorus atom does not coincide with the bisector of the plane of the OPO fragment of the heterocycle and is not perpendicular to it.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 214–217, January, 1991.     

Reaction of 2-Tetrafluoropropoxy-5,6-benzo-1,3,2-dioxaphosphorinan-4-one with Pyruvonitrile

The reaction of pyruvonitrile with 2-tetrafluoropropoxy-5,6-benzo-1,3,2-dioxaphosphorinan-4-one results mainly in the enlargement of the starting heteroring to form 4-cyano-4-methyl-2-tetrafluoropropoxy-6,7-benzo-1,3,2⁵-dioxaphosphepin-5-one 2-oxide as a mixture of two diastereomers (14:1) along with minor amounts of 3-cyano-3-methyl-2-tetrafluoropropoxy-6,7-benzo-1,4,2⁵-dioxaphosphepin-5-one 2-oxide.     

Reaction of 4-Oxo-5,6-benzo-1,3,2-dioxaphosphinin-2-yl Isocyanate with Dialkyl Arylcarbonylphosphonates

Russian Journal of General Chemistry -     

Crystal and molecular structure of 2-phenyl-2-thiono-5,6-(4′,5′-dimethylbenzo)-1,3,2-dithiaphosphepine and 2-methoxy-2-oxo-5,6-benzo-1,3,2-dioxaphosphepine

A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Branch, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 31, No. 5, pp. 75–80, September–October, 1990.     

Synthesis of 1,4,2-dioxaphosphepanes by the reaction of 2-fluoroalkoxy-4-oxo-5,6-benzo-1,3,2-dioxaphosphorinanes with chloral

The reaction of 2-fluoroalkoxy-5,6-benzo-1,3,2-dioxaphosphorinanes with chloral leads to the formation of ring expansion products with a P-C bond, namely, 2-fluoroalkoxy-2,5-dioxo-3-trichloromethyl-6,7-benzo-1,4,2-dioxaphosphepanes with high stereoselectivity.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1676–1678, July, 1991.     

Conformational analysis of 1,3,2-dioxaphospholan-yl and 4,5-benzo-1,3,2-dioxaphosphol-2-yl 2,2,2-trifluoroacetate

Conformational analysis of 1,3,2-dioxaphospholan-2-yl 2,2,2-trifluoroacetate and 4,5-benzo-1,3,2-dioxaphosphol-2-yl 2,2,2-trifluoroacetate was carried out using the method of dipole moments and quantumchemical calculations (DFT B3LYP/6-31G*). Both compounds are found to exist as an axial conformer with preferably syn arrangement of the carbonyl group and the lone electron pair.     

Dimers of 4,5-benzo-1,3,2-oxazaphospholenes

Conclusions 2-Alkyl-2-hydro-4,5-benzo-1,3,2-oxazaphospholenes, which are formed by the prototropic isomerization of 2-alkyl-4,5-benzo-1,3,2-oxazaphospholanes, exist as the dimers. The dimerization process is reversible and in polar solvents is shifted toward the oxazaphospholanes. The 2-alkyl(alkoxy)-2-(-cyanoethyl)-4,5-benzo-1,3,2-oxazaphospholanes have a dimer structure.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1150–1152, May, 1979.     

Reaction of 2-tert-butoxy-4,5-benzo-1,3,2-dioxaphospholane with tribromoacetaldehyde

The reaction of 2-tert-butoxy-4,5-benzo-1,3,2-dioxaphospholane with tribromo-acetaldehyde proceeds by initial halophilic attack on the bromine atom, leading to a product with retention of the P-Br bond (pyrocatechol bromophosphate) and an anion exchange product (pyrocatechol dibromovinylphosphate), and by initial attack at the carbon atom of the C=O group, which is accompanied by the elimination of isobutylene to form an -hydroxyphosphonate.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1909–1912, August, 1989.     

Reaction of 2-ethyl-4,5-benzo-1,3,2-oxazaphospholane with mercaptans

Conclusions The reaction of 2-ethyl-4,5-benzo-1,3,2-oxazaphospholane with mercaptan proceeds to give the monocyclic phosphorane with a P-N bond and the thioamidophosphonite, the product of opening the oxazaphospholane ring at the oxygen-phosphorus bond.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 224–226, January, 1977.