Über die Kristallstruktur von (C6H5)3SiSH und (C6H5)3SiSBr und die Darstellung des Iodsulfans (C6H5)3SiSI

The Crystal Structure of (C₆H₅)₃SiSH and (C₆H₅)₃SiSBr and the Preparation of the Iodosulfane (C₆H₅)₃SiSI The preparation of the halogenosulfanes Ph₃SiSBr and Ph₃SiSI from Ph₃SiSH and N-halogenosuccinimide is reported. They are characterized by vibrational spectroscopic measurements. Ph₃SiSBr crystallizes in space group P1 with a = 899.3(8) pm, b = 941.3(7) pm, c = 1 051.4(7) pm, α = 109.88(5)°, β = 99.23(6)°, γ = 96.78(6)° and Z = 2. Ph₃SiSH crystallizes in space group P2₁/c with a = 1 879.4(8), b = 966.3(5), c = 1 845.2(9), β = 107.84(4), Z = 8. The halogenosulfanes decompose in polar solvents by formation of sulphur and triphenylsilanhalide.     

6(5H)-phenanthridinones. III. halo-6(5H)phenanthridinones

Halogenation of 6(5H)-phenanthridinone or its 3,8-dihalo derivatives with N-bromo or N-chlorosuccinimide in dimethylformamide gives the corresponding 2-halophenanthridinones (I,V,XI-XIV). Further halogenation of 2-halo-6(5H)-phenanthridinone with the appropriate N-halosuccinimide, in the same medium, gives the corresponding 2,4-dihalo derivatives (II,VI). NXS/DMF is found to be a very convenient halogenating system in these preparations. 1,3,8-Trihalo-6(5H)-phenanthridinones (XIX,XX) are prepared from the 1-nitro derivatives which are obtained by a Schmidt rearrangement of 2,7-dihalo-4-nitro-9-oxofluorenes. Similarly, rearrangement and further reaction of 2-nitro-5-chloro-9-oxofluorene (XXI) leads to 3,10-dichloro-6(5H)-phenanthridinone (XXIV). UV absorptions as well as selected IR absorptions of these 6(5H)-phenanthridinones are described.     

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.     

Synthese und Kristallstrukturen der Bismutchalkogenolate Bi(SC6H5)3, Bi(SeC6H5)3 und Bi(S‐4‐CH3C6H4)3

Synthesis and Crystal Structures of Bismuth Chalcogenolato Compounds Bi(SC₆H₅)₃, Bi(SeC₆H₅)₃, and Bi(S‐4‐CH₃C₆H₄)₃ Bismuth(III) acetate reacts with thiophenol in ethyl alcohol at 80 °C to yield Bi(SC₆H₅)₃ ( 1 ). Slow cool down of the deep yellow mixture lead to the formation of orange crystals of 1 . The homotype phenylselenolato compound of bismuth Bi(SeC₆H₅)₃ ( 2 ) has been prepared by the reaction of BiX₃ (X = Cl, Br) with Se(C₆H₅)SiMe₃ in diethyl ether. In the same way as Bi(SC₆H₅)₃ ( 1 ) the reaction between bismuth(III) acetate and 4‐tolulenethiole results in red crystals of Bi(S‐4‐CH₃C₆H₄)₃ ( 3 ). In consideration of three longer Bi–E distances (intermolecular interactions, E = S; Se) the Bi(EPh)₃ molecules form via face‐linked octahedra 1‐dimensional chains in the crystal lattice, while for 3 the 1‐dimensional chain is formed by face‐linked trigonal prisma. We reported herein the synthesis and structures of Bi(SC₆H₅)₃ ( 1 ), Bi(SeC₆H₅)₃ ( 2 ), and Bi(S‐4‐CH₃C₆H₄)₃ ( 3 ).     

Stereospecific and chemospecific interconversions of the rhenium alkylidene [(η-C5H5)Re(NO)(PPh3)(CHC6H5)]+PF6− and the alkylrhenium (η-C5H5)Re(NO)(PPh3)(CH(OCH3)C6H5)

Addition of methoxide to either geometric isomer of the benzylidene complex [(η-C₅H₅)Re(NO)(PPh₃)(CHC₆H₅)]⁺PF₆^? (1t, 1k) affords (η-C₅H₅)Re(NO)(PPh₃)(CH(OCH₃)C₆H₅ (2t, 2k) in which a new chiral center has been generated stereospecifically or with high stereoselectivity. Reaction of 2t and 2k with Ph₃C⁺PF₆^? results in the chemospecific abstraction of a methoxy group and the stereospecific regeneration of 1t and 1k, respectively.     

Synthese und Kristallstruktur von (C5H5)Mo(CO)3(AuPPh3) und [(C5H5)Mo(CO)2(AuPPh3)4]PF6

Synthesis and Crystal Structure of (C₅H₅)Mo(CO)₃(AuPPh₃) and [(C₅H₅)Mo(CO)₂(AuPPh₃)₄]PF₆ CpMo(CO)₃(AuPPh₃) is obtained by the reaction of Li[CpMo(CO)₃] with Ph₃PAuCl at ?95°C in CH₂Cl₂. It crystallizes in the monoclinic space group C2/c with a = 2625.1(7), b = 883.2(1), c = 2328.4(7) pm, β = 116.39(1)° und Z = 8. In the complex the AuPPh₃ group is coordinated to the CpMo(CO)₃ fragment with a Au? Mo bond of 271,0 pm. The Mo atom thus achieves a square pyramidal coordination with the center of the Cp ring in apical position. CpMo(CO)₃(AuPPh₃) reacts under uv irradiation with an excess of Ph₃PAuN₃ to afford the cluster cation [CpMo(CO)₂(AuPPh₃)₄]⁺. It crystallizes as [CpMo(CO)₂(AuPPh₃)₄]PF₆ · 2 CH₂Cl₂ in the orthorhombic space group P2₁2₁2₁ with a = 1553.9(1), b = 1793.8(2), c = 2809.8(7) pm und Z = 4. The five metal atoms form a trigonal bipyramidal cluster skeleton with the Mo atom in equatorial position. The Mo? Au distances range from 275.5 to 280.8 pm, and the Au? Au distances are between 281.2 and 285.6 pm.