6(5H)-phenanthridinones. II. Preparation of substituted 6(5h)-phenanthridinones from 9-oxofluorenes

A number of 6(5H)-phenanthridinones have been conveniently prepared from 9-oxofluorenes through the Schmidt reaction. It has been found that all amino and nitro 9-oxofluorenes thus far tried gave substituted 6(5H)-phenanthridinones with the amino or nitro group situated in the benzene ring attached to the nitrogen of the lactam group. UV and IR spectral data are presented for these compounds.     

Synthesis and structure of nitro-substituted 6(5H)-phenanthridinones

Methods for the preparation of nitro-substituted 6(5h)-phenanthridinones were examined. The nitration of 6(5H)-phenanthridinone, 5-methyl-6-(5H)- phenanthridinone, and 2-bromo-6(5H)-phenanthridinone was studied, and 2-, 3-, 4-nitro-, 2,4-, 2,8-, 4,8-dinitro-, 2,4,8-trinitro-, and 2,4,8,10-tetranitro-6(5H)-phenanthridinones, 2,4,8-trinitro- and 2,4,8,10-tetranitro-6-(5H)-phenanthridinones, and 2-bromo-4,8-dinitro- and 2-bromo-4,8,10-trinitro-6-(5H)-phenanthridinones were obtained. Proton magnetic resonance spectroscopy was used to identify the structure and predict the orientation of substitution in the nitration of 6(5H)-phenanthridinone and its nitro-substituted derivatives. The distribution of the electron density in these compounds was evaluated from an analysis of the chemical shifts of the protons.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1106–1113, August, 1985.     

Synthesis and structure of bromonitro-6(5H)-phenanthridinones

Treatment of 2-bromo-6(5H)-phenanthridone with nitrating mixture or fuming nitric acid results in nitration, debromination, and bromination in the 10-position. The brominating agent is apparently Br⁺, formed in the reaction mixture following replacement of the bromine in the 2-position by a nitro-group. Monocrystals of 2-bromo-1,4,8-trinitro-6(5H)-phenanthridinone and 10-bromo-2,4,8-trinitro-6(5H)-phenanthridinone have been subjected to x-ray diffraction examination. PMR has been used for structural identification.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 789–795, June, 1990.We thank A. N. Sobolev for assistance in calculating the structure of (III).     

Synthesis and structures of 10-hydroxy- and 10-acetoxy-6(5H)phenanthridinones

Treatment of 2,4,8,10-tetranitro-6(5H)-phenanthridinone with hexamethylphosphoric triamide leads to intermolecular nucleophilic substitution of the nitro group by a hydroxy group, the source of which is the water contained in the solvent, to give 10-hydroxy-2,4,8-trinitro-6(5H)-phenanthridinone. An intramolecular interaction with the participation of a proton of the aromatic ring and an oxygen atom of the hydroxy or acetoxy group of the 10-hydroxy- or 10-acetoxy-2,4,8,-trinitro-6(5H)-phenanthridinone, the properties of which are characteristic for an intramolecular hydrogen bond, was detected by x-ray diffraction analysis and PMR spectroscopy.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 314–319, March, 1987.     

4(And 5)-cyclopropylamino-5(and 4)halo-3(2H)pyridazinones. Formation and characterization of isomers

The reactions of 4,5-dihalo-3(2H)pyridazinones with ammonia and amines gave mixtures of 5-amino-4-halo- and 4-amino-5-halo-3(2H)pyridazinones separated by chromatography. Structures were elucidated by means of retention values (R_f) and confirmed by independent synthesis.     

Beiträge zur Chemie des Phosphors. 67. Zur Kenntnis der Cyclotriphosphane (PC6H5)3, (PC6H5)2(PC2H5) und (PC6H5)2(PCH3)

Contributions to the Chemistry of Phosphorus. 67. About the Cyclotriphosphanes (PC₆H₅)₃, (PC₆H₅)₂(PC₂H₅), and (PC₆H₅)₂(PCH₃) The reaction of (CH₃)₃Si(C₆H₅)P? P(C₆H₅)Si(CH₃)₃ with RPCl₂ (R = C₆H₅, C₂H₅, CH₃) yields the cyclotriphosphanes (PC₆H₅)₃ 1 , (PC₆H₅)₂(PC₂H₅) 3 , and (PC₆H₅)₂(PCH₃) 4 , respectively. Besides, the corresponding homo- and mixed-substituted cyclotetraphosphanes, cyclopentaphosphanes, and cyclohexaphosphanes are formed. The relative concentrations of the cyclotriphosphanes in the reaction mixtures decrease continuously, whereas those of the cyclopentaphosphanes increase. The reasons for these ring-interconversion reactions of the cyclophosphanes (PR)_n are discussed. The cyclotriphosphanes 1, 3 , and 4 are characterized by ³¹P chemical shifts between +130 and +160 ppm that are at considerable high field compared to open-chain triphosphanes and cyclophosphanes of different ring-size. The substituents R are situated on both sides of the P₃-ring plane, thus giving rise to two diastereomers of 3 that are observed simultaneously in the statistically expected ratio. The ³¹P n.m.r. parameters of 1 and 3 are reported and discussed.     

m -Terphenyl derivative of titanium(III): Cp2TiR (Cp=C5H5; R =2,6-(4-MeC6H4)2C6H3)

The title compound, Cp₂TiR (Cp=C₅H₅; R=2,6-(4-MeC₆H₄)₂C₆H₃), 1, was prepared by reaction of RLi with [Cp₂TiCl]₂. Compound 1 was characterized by elemental analysis, EPR, and single crystal X-ray crystallography. The title compound crystallizes in the monoclinic space group C2/c with the following unit cell dimensions: a=11.1466(7) Å, b=16.4429(11) Å, c=13.0786(8) Å; b=106.2040(10)^°;V=2301.9(3) ų. The EPR spectrum of 1 displays two signals, a high field signal at g=1.979 and a lower field signal at g=1.959. Significantly, 1 is a sterically encumbered m-terphenyl-stabilized trivalent titanocene paramagnetic complex and may be a practical one-electron reducing reagent.     

Zur disproportionierung der phenylfluorphosphane (C6H5)2PF und (C6H5)PF2

Ph₂P-PF₂Ph₂ has been identified by means ¹⁹F- and ³¹P- NMR spectroscopy as an intermediate product of the disproportionation of Ph₂PF. The disproportionation is catalyzed by acids. The reaction mechanism is discussed. PhPF₂ disproportionates faster in solution in acetonitrile than neat, forming (PhP)₆, instead of (PhP)₅.     

Rate constants for tsomerization of C6H5C(SC6H5)2 ĆH2 radicals to C6H5Ć(SC6H5)CH2SC6H5 radicals based on EPR data

Conclusions The parameters of the Arrhenius equation for the isomerization of PhC(SPh)₂H₂ radicals to Ph(SPh)CH₂. SPh radicals are in agreement with an intramolecular character of the rearrangement, with a 1,2-migration of the thiyl group. These parameters were calculated on the basis of the data that were obtained by the EPR method in the range 10–70°.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2596–2597, November, 1982.     

Reaction of 2-dimethylaminomethylene-1,3-diones with dinucleophiles. III. Synthesis of 5-acylpyrimidines and 7,8-dihydroquinazolin-5(6H)-ones

The reaction of open-chain and cyclohexane sym-2-dimethylaminomethylene-1,3-diones with amidines and guanidine in refluxing ethanol gave, generally in good yields, a series of 5-acylpyrimidines and 7,8-dihydroquinazolin-5(6H)-ones, respectively. With formamidine (and in part acetamidine), 2-formylimino-1,3-diones were formed in general, as sole products or mixtures with the corresponding pyrimidines or dihydroquinazolinones.     

Double cerium(III) cerium(IV) sulfate K5Ce2(SO4)6·H2O

All Union Scientific Research Institute for Chemical Reagents and Highly Pure Chemical Substances. Translated from Zhurnal Strukturnoi Khimii, Vol. 30, No. 1, pp. 135–140, January–February, 1989.     

A thermal and structural study on Lanthanum Hexacyanocobaltate(III) pentahydrate,La[Co(CN)6]·5H2O. Part III

On dehydration of La[Co(CN)₆]·5H₂O, the color of the complex, changes from white to pale blue at around 230°C. Heating the pale blue specimen, the color changes to deep blue at around 290°C. This deep blue specimen is easily rehydrated to a pink one. As reported previously, in the pale blue specimen, Co³⁺ ions are situated in the center of the D_4h crystal field formed by six CN^- ions. The deep blue specimen is due to the presence of [Co(CN)₄]^2- ions in which Co²⁺ was situated in a T_d coordination field formed by four CN^- ions and the Co-C bond length is 1.67 Ĺ. The pink species corresponded to trans-[Co(CN)₄(H₂O)₂]^2- and the bond lengths of Co-C and Co-O are 1.89 and 1.85 Ĺ, respectively. The Raman spectra of the complex observed at 25°C displays two bands at 2157 and 2176 cm^-1 associated with the vibration of C-N bond, and the band of 2157 cm^-1 was split into two bands, 2150 and 2156 cm^-1, at around 100°C. When the complex was heated to around 230°C, three new bands were observed at 2103, 2116 and 2141 cm-1. The bands of 2103 and 2116 cm^-1 were assigned to the stretching vibration of C=N bonding to Co²⁺. The band of 2141 cm^-1 was assigned to the stretching vibration of the inverted CN^- as follows: Co-C=N-La→Co-N=C-La. The activation energy for the inversion of CN^- was estimated as 67 kJ mol^-1. This revised version was published online in August 2006 with corrections to the Cover Date.