Spatial structure of 5-phenyl-5-oxo-2,4,6-triisopropyl-1,3,5-dioxa phosphorinane

Conclusions By means of x-ray structure analysis, it has been shown that the stereoisomer of 5-phenyl-5-oxo-2,4,6-triisopropyl-1,3,5-dioxaphosphorinane with mp 215°C has the chair conformation with all equatorial substituents of the ring atoms and axial substituents of the phosphoryl group. The conformations of the isopropyl groups are retarded relative to the ring bonds. The benzene ring at the P atom is perpendicular to the plane of the heterocycle.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No.3, pp. 599–603, March, 1982.     

Synthesis and steric structure of 2,2-disubstituted 5-phenyl-1,3,5-dioxaphosphorinanes

Conclusions Phenylbis(l-ethoxyalkyl)phosphines and 2,2-disubstituted 5-phenyl-l,3,5-dioxaphosphorinanes, with their conformational equilibrium shifted in the direction of the form with an axial orientation of phenyl at the phosphorus atom, were obtained by the reaction of phenylbis(hydroxymethyl)phosphine with aldehyde and ketone acetals, respectively.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2506–2509, November, 1986.     

Synthesis and equilibrium of stereoisomers of 5-phenyl-2-ethoxy-1,3,5-dioxaphosphorinane

Conclusions The reaction of bis(hydroxymethyl)phenylphosphine with orthoformic ester gave 5-phenyl-2-ethoxy-1, 3, 5-dioxaphosphorinane, representing a mixture of two stereoisomers. The preferred conformations of these differ in the orientation of the phenyl residue on the phosphorus atom. The stereoisomer with the equatorial orientation of the phenyl radical predominantes in the equilibrium.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 418–422, February, 1986.     

7-Bromo-5-phenyl-1,2-dihydro-3H-1,3,5-benztriazepin-2-one

7-Bromo-5-phenyl-1,2-dihydro-3H-1,4-benztriazepin-2-one was obtained by thermolysis of the syn-4-phenylsemicarbazone of 2-aminobenzophenone. Its molecular and crystal structure were established by X-ray crystallography. The nature of the hydrogen bonds between molecules of the compound in solution and in the crystalline state was determined by IR spectroscopy and X-ray crystallography.     

Conformational equilibrium of N,N-disubstituted 5-phenyl-1,3,5-diazaphosphorinanes and their derivatives

Conclusions In the conformational equilibrium of N,N-disubstituted 5-phenyl-1,3,5-diazaphosphorinanes and their oxides and sulfides forms can exist with an axial substituent on one of the heteroatoms, as well as a form with all equatorial substituents at the P and N atoms.Translated from Izvestiya Akademii Nauk SSSR, Seriyra Khimicheskaya, No. 7, pp. 1539–1544, July, 1981.     

Study of equilibrium of 5-phenyl-2,4,6-trimethyl-1,3,5-dioxaphosphorinane stereoisomers and their derivatives

Conclusions We determined the conformational free energy of a phenyl substituent on a tri- and tetracoordinated phosphorus atom in a 2,4,6-trimethyl-1,3,5-dioxaphosphorinane ring.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1911–1916, August, 1978.     

Twist form in equilibrium of stereoisomers of 5-phenyl-2,4,6-triisopropyl-1,3,5-dioxaphosphorinane and its derivatives

Conclusions In the equilibrium of 5-phenyl-2,4,6-triisopropyl-1,3,5-dioxaphosphorinane and its derivatives the stereoisomer with nonequivalent protons on the carbon atoms attached to phosphorus is found predominantly in the twist form.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1630–1634, July, 1980.     

Rearrangement of benzylsulfanyl-substituted 2-aza-1,3,5-triene into 5-phenyl-4,5-dihydro-1,3-thiazole in the t-BuOK-THF-DMSO system

Benzylsulfanyl-substituted 2-aza-1,3,5-triene prepared according to one-pot procedure from methoxyallene, isopropyl isothiocyanate, and benzyl bromide underwent unexpected rearrangement in the superbasic t-BuOK-THF-DMSO system with formation of 2-[(Z)-1-methoxyprop-1-en-1-yl]-4,4-dimethyl-5-phenyl-4,5-dihydro-1,3-thiazole via α-deprotonation of the benzylsulfanyl substituent, followed by intramolecular [1,5]-cyclization. Concurrent deprotonation of methyl group in the ketone imine fragment and subsequent [1,7]-electrocyclization of the resulting azatriene carbanion afforded 2-(benzylsulfanyl)-3-methoxy-7-methyl-4,5-dihydro-3H-azepine and 6-methoxy-2-methyl-3H-azepine.     

Synthesis and1H and31P NMR spectral characteristics of 2-substituted and 2,2-disubstituted 5-phenyl-5-thio-1,3,5-dioxaphosphorinanes

Conclusions Treatment of phenylbis(hydroxymethyl)phosphine sulfide with acetals and ketals gives the corresponding 2-substituted and 2,2-disubstituted 5-phenyl-5-thio-1,3,5-dioxaphosphorinanes in which the P-Phenyl substituent occupies an axial position.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 418–422, February, 1987.     

Molecular and crystal structure of rel-(4R,6R)-5-thio-5-phenyl-2,4,6-triisopropyl-1,3,5-dioxaphosphorinane

Conclusions The stereoisomer of 5-thio-5-phenyl-2,4,6-triisopropyl-1,3,5-dioxaphosphorinane with mp 124°C has twist conformation with equatorial substituents at C⁴ and C⁶ and a pseudoequatorial phenyl group.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1056–1060, May, 1984.     

Formylation of 2-phenyl- and 3-phenyl-5-hydroxybenzofuran derivatives

The Vilsmeier formylation of 2-phenyl- and 3-phenyl-5-hydroxybenzofuran derivatives was studied. It is shown that 2-phenyl-5-methoxybenzofuran is formylated in the 4 position, whereas 3-phenyl-5-methoxybenzofuran is formylated in the 2 position.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1023–1024, August, 1976.     

5-Hydroxy-3-phenyl-5-vinyl-2-isoxazoline and 3-phenyl-5-vinylisoxazole: synthesis and reactivity

5-Hydroxy-3-phenyl-5-vinyl-2-isoxazoline has been synthesized by reacting benzonitrile oxide with the enolate ion of methyl vinyl ketone. From 5-hydroxy-5-vinyl-2-isoxazoline, 5-vinylisoxazole was then quantitatively obtained by dehydration-aromatization under acidic conditions. Similar results, though not quantitative, were also found by treatment in 2-propanol under basic conditions (i-PrOH/H₂O, Na₂CO₃, reflux). In contrast to 2-propanol, reactions performed in methanol (and, in part, those carried out in ethanol) revealed a more complex behaviour, the nucleophilic addition of ROH onto the vinyl group being mainly observed. Nucleophilic addition was also found with alkyllithiums. The mechanism of the nucleophilic addition is discussed. Epoxidation and further reaction with benzonitrile oxide of both 3-hydroxy-5-phenyl-5-vinyl-2-isoxazoline and 3-phenyl-5-vinylisoxazole are also described.     

Vibrational assignments and theoretical calculations of 1-phenyl-5-mercaptotetrazole and 1-phenyl-5-mercaptotetrazolate

The infrared and Raman spectra of 1-phenyl-5-mercaptotetrazole (PMT) and 1-phenyl-5-mercaptotetrazole sodium salt in the solid state and in solution have been measured. Detailed vibrational assignments of PMT and 1-phenyl-5-mercaptotetrazolate (PMTA) have been performed. In order to give a firmer basis to the interpretation of the vibrational spectra, harmonic wavenumbers of PMT and PMTA have been calculated by means of MP2 and DFT/BPW91 calculations. The DFT calculations provide a satisfactory agreement between the calculated and observed wavenumbers without using scaling factors. Experimental evidence shows that PMT is present in the thione tautomer both in the solid state and in solution of polar solvents.