bluuebunny/crossref_metadata_2025 huggingface dataset:
Toward molecular wire: Synthesis, crystal, molecular, and π‐electronic structure of 1,7‐bis(aryl)‐1,3,5,7‐tetraaza‐2,4,6‐trithia‐1,2,5,6‐heptatetraenes
Authors: Zibarev Andrey V. , Miller Alexey O. , Gatilov Yuri V. , Furin Georgii G.
Published: January 2005

The title compounds were obtained by the reaction of 1‐aryl‐3‐trimethylsilyl‐1,3‐diaza‐2‐thiaallenes with dichloromonosulfane or 1‐aryl‐4‐(1‐phtalimidyl)‐1,3‐diaza‐2,4‐dithia‐1,2‐butadienes in the presence of CsF. The latter route also afforded nonsymmetric derivatives. In contrast, the reaction of N,N,N′,N′‐tetrakis(trimethylsilyl)diaminosulfane with S,S‐dichloro‐N‐aryliminosulfuranes (1:2) led to 1,3‐bis(aryl)‐1,3‐diaza‐2‐thiaallenes and cyclotetra(azathiene). As shown by the X‐ray structure analysis, the molecule of the title compound with Ar = Ph is planar, with configuration of the azathiene chain being similar to that of poly(azathiene) (SN)x. The MNDO calculations indicate that most of the π‐MOs of this compound, including the frontier ones, are delocalized throughout the whole molecule. The data obtained confirm the possibility of creating molecular wire for molecular electronic devices on the basis of extended acyclic azathienes. An attempt to synthesize more extended compounds than the title ones resulted in spontaneous shortening of their azathiene chains.
The reaction of decaborane with hydrazoic acid: A novel access to azaboranes
Authors: Müller J. , Paetzold P. , Boese R.
Published: January 2005

The reaction of B10H12(SMe2)2 (1) with HN3 yields arachno‐B10H12(N3)(NH2) (2), a product with a μ‐NH2 group. Compound 2 can be hydrolysed to give the known arachno‐B9H13(NH3) (3). nido‐NB9H11(N3) (4) is formed from 2 by a deprotonation/protonation sequence. The azaborane nido‐NB10H13 (5) is a product of the thermolysis of 2. The structures of 2–5 are elucidated by 2‐D COSY 11B–11B NMR spectra; the structure of 2 is also elucidated by an X‐ray structure analysis.
Synthesis and characterization of (Me3Si)2AsCH2RCH2As(SiMe3)2 (R = CH2, SiME2) and
Authors: Holley W. K. , Pasterczyk J. W. , Pitt C. G. , Wells R. L.
Published: January 2005

The synthesis and characterization of (Me3Si)2AsCH2RCH2As(SiMe3)2 [R = CH2 (1), SiMe2 (2)] is described. Compound 1 reacts with four equivalents of Ph2GaCl to produce (3), whose structure was deduced by use of 1H and 13C{1H} NMR spectroscopy.
Samarium (II) diiodide‐induced reductive cleavage of SeSe and TeTe bond in diphenyl diselenide and ditelluride leading to a samarium phenylselenolate and tellurolate: Preparation of unsymmetrical alkylphenyl selenides and tellurides
Authors: Fukuzawa Shin‐Ichi , Niimoto Yasuhiko , Fujinami Tatsuo , Sakai Shizuyoshi
Published: January 2005

Diphenyl diselenide and diphenyl ditelluride were reduced by samarium (II) diiodide in tetrahydrofuran‐hexamethylphosphoric triamide to produce samarium phenylselenolate and samarium phenyltellurolate, respectively. This new selenolate or tellurolate anion species reacted smoothly with alkyl, allyl, and benzyl halides to give alkyl‐, allyl‐, and benzylphenyl selenides or tellurides in good yields under mild and neutral conditions. The samarium selenolate reacted with α‐halo ketones to give the corresponding α‐phenylseleno ketones. 1,4‐Addition with α,β‐enones proceeded to give 3‐phenylseleno ketones in moderate yields. Isolation of phenylselenotributyltin or phenylseleno‐trimethylsilane by transmetalation with tributyltin iodide or trimethylchlorosilane, respectively, suggested the presence of the samarium selenolate species.
Reactivity in molecular crystals: Radical formation in chiral phosphorus compounds
Authors: Aagaard Olav M. , Janssen René A. J. , de Waal Bas F. M. , Buck Henk M.
Published: January 2005

Molecular mechanics calculations, using the AMBER program (version 3.0), are presented on the radiogenic electron‐capture radical formation in the crystalline chiral organophosphorus compounds (2R,4S,5R) and (2S,4S,5R) 2‐chloro‐3,4‐dimethyl‐5‐phenylphospholidine 2‐sulfide (respectively 1 and 2). Geometry optimization of the corresponding radical anion structures and their respective crystal surroundings reveals an increase of the Van der Waals interactions, which is significantly larger in compound 2 than in 1. This is in good agreement with previous single‐crystal ESR experiments and molecular interactions calculations without geometry optimization [1].
A novel synthesis of α,β‐unsaturated phosphonates
Authors: SkowrońNska Aleksandra , Dybowski Piotr
Published: January 2005

A stereoselective synthesis of α,β‐unsaturated phosphonates based on the reaction of S‐(β‐oxoalkyl)‐dithiophosphates and Se‐(β‐oxoalkyl)selenophosphates with sodium dialkyl phosphites is described.
The extension of the mechanistic concept of the nucleophilic catalysis in the silicon chemistry to some reactions of the P(III) center: Analogies between silylation and phosphorylation
Authors: Chojnowski Julian , Cypryk Marek , Fortuniak Witold
Published: January 2005

Many observations prove that a number of silylation reactions of a trialkylsilyl halide‐uncharged base system occur with the transient formation of a 1:1 tetrahedral silicon ionic complex of the silyl halide with the base. Some catalytic processes of phosphorylation of protonic substrates with tricoordinate phosphorus halides in mixture with an uncharged base show similar features to these silylation reactions, implying that a similar mechanism may operate. It was demonstrated that Ph2PCl phosphorylates t‐BuOH faster under catalysis with 4‐N,N‐dimethylamino pyridine or N‐methylimidazole than in the presence of Et3N by a factor of 400 and 33, respectively. The catalytic phosphorylation process exhibits a very low activation energy and a high negative value of entropy of activation. The interaction of the uncharged bases with model tricoordinate phosphorus halides was demonstrated to lead to the formation of ionic 1:1 complexes without changing the coordination number of phosphorus, in full analogy to the silyl halide complex formation. Finally, the interaction of phosphorous tris(dimethylamide) with a silyl iodide and a phosphorous iodide results in both cases in the formation of the ionic 1:1 complex, which also leads to analogous reactions of exchange of the amide group with iodide. These close similarities imply that some phosphorylation reactions with tricoordinate phosphorus halides catalyzed with uncharged bases occur via a tricoordinate phosphorus cation intermediate.
Two new syntheses of the “phospha‐wittig” reagents
Authors: Bauer Siegfried , Marinetti Angela , Mathey François
Published: January 2005

The secondary phosphorylphosphane complexes used in the synthesis of phosphaalkene complexes from carbonyl compounds by the so‐called „phospha‐Wittig”︁ reaction can be obtained by two routes. In the first one, a primary lithiophosphine complex is condensed with a chlorophosphite. The resulting PP compound is oxidized at the free phosphorus by 3‐chloroperbenzoic acid. In the second one, bis(phosphoryl)phosphane complexes are allowed to react with sodium methylate in methanol or with water. One of the two PP bonds of the starting produt is thus cleaved to give the „phospha‐Wittig”︁ reagent. Both routes give better yields and are less sensitive to steric hindrance than the previously described method.
Synthesis of benzo‐1,3‐ditellurole and its precursors
Authors: Sadekov I. D. , Rivkin B. B. , Gadjieva P. I. , Minkin V. I.
Published: January 2005

Poly(o‐phenyleneditelluride) 6 has been prepared by the reduction of 1,2‐bis(trichlorotelluro)benzene obtained by treatment of 1,2‐bis(trimethylsilyl)benzene with TeCl2. The reduction of 6 with NaBH4 in ethanol solution affords sodium benzene‐1,2‐ditellurolate, which, upon treatment with methylene bromide, forms benzo‐1,3‐ditellurole in 40–47% yield. Benzo‐1, 3‐ditellurole has also been synthesized in 18–20% yeild by the reaction of 1,2‐bis(trimethylslyl)benzene with bis(trichlorotelluro)methane, with subsequent reduction of the product, 1,1,3,3‐tetrachlorobenzo‐1,3‐ditellurole.
Bimanes 28: Extraction of sulfur from fluorescent models for biological thiols
Authors: Radkowsky Annette E. , Marciano Daniele , Shalev Deborah E. , Kosower Nechama S. , Zipser Judith , Kosower Edward M.
Published: January 2005

Sulfur extraction from the tripeptide thiol, glutathione (α‐glu‐cys‐gly) (1) via reaction with syn‐(1‐bromo‐ethyl, methyl)bimane (2) yields glutathione slfide and the thiabridged bimane, μ(S)‐syn‐(methylmethylene, methyl)bimane (3) [1]. The reaction with 2 has been extended to dithiols as models for important biological thiols such as reduced trypanothione. The fluorescent dithiols were derived through reductive cleavage with triphenylphosphine (tetrahydrofuan, Hcl−Kbr solution, pH 1.5) of the dithiatriclic bimane esters, μ(O2C(CH2)SS(CH2)nCO2)‐syn‐(CH2,CH3)B, n = 1, 2, 3, prepared from syn‐(bromomethyl, methyl)bimane (4) and the corresponding dithiadicarboxylic acids. Sulfur extraction led to 3 and the cyclic sulfide derived from the dithiol in moderate yields. The dithiols, dithiothreitol and dithioerythritol, also yielded moderate amounts of 3. Sterically hindered thiols (e.g., those in hemoglobin) gave 3 in lower yields. Treatment of human red blood cells and red cells membranes (hemoglobin‐free ghosts) with 2 gave rise to some 3. A side product in some reactions was the oxabridged bimane, μ(O)‐syn‐(methylmethylene, methyl)bimane.
Synthesis, characterization, and solution properties of new heterocyclic tellurium compounds based on 5,6‐dimethyl‐1,3‐dihydro‐2‐telluraindene
Authors: Al‐Rubaie Ali Z. , Al‐Masoudi Eman A.
Published: January 2005

The synthesis and characterization of a new range of heterocyclic tellurium compounds based on 5,6‐dimethyl‐1,3‐dihydro‐2‐telluraindene are reported. Conductivity measurements of most compounds in dimethylsulfoxide (DMSO) and N,N‐dimethylformamide (DMF) showed considerable ionic character in both solvents. 1H and 13C NMR studies indicated that the telluronium salts are stable to reductive elimination and no reaction between solute and solvent was observed. Benzyl and allyl telluronium salts are exceptional. Infrared and mass spectral data are reported and discussed.
Synthesis of functionalized phosphinines: Aromatization of Diels‐Alder adducts of P‐chlorobis(trimethylsilyl)methylenephosphine
Authors: Abbari Mustapha , Ko Yeung Yat Cheng Yeung Lam , Carriéa Robert
Published: January 2005

The Diels‐Alder adducts of functionalized dienes with P‐chloro‐bis(trimethylsilyl)methylenephosphine can be aromatized, except in a few particular cases, thus opening a general route to functionalized phosphinines. The aromatization procedure differs with the substituents. Intermediates such as secondary cyclic phosphines could be characterized and even isolated. In some cases, aromatization and 1,5 sigmatropic shift of a trimethylsilyl group were observed and hydrogenolysis of the CSi bond as well.
Crystal structure and theoretical investigation of the configurations of 1,3‐dichloro‐1,3‐diazetidine‐2,4‐dione and 1,3‐bis(trimethylsilyl)‐1,3‐diazetidine‐2,4‐dione
Authors: Belaj Ferdinand , Nachbaur Edgar , Faleschini Gottfried , Janoschek Rudolf
Published: January 2005

Crystal structures of 1,3‐dichloro‐1,3‐diazetidine‐2,4‐dione (1) and the hitherto unknown compound 1,3‐bis(trimethylsilyl)‐1,3‐diazetidine‐2,4‐dione (2) have been determined by X‐‐ray crystallography: 1: (CINCO)2, Mr = 154.94, T = 295 K, orthorhombic, Pbca, a = 7.699(1), b = 6.706(1), c = 10.598(2) Å, V = 547.2(2) Å3, Z = 4, dx = 1.881 g/cm3, μ = 10.9 cm−1, R = 3.14%, Rw = 2.82% (660 observations, 38 parameters). 2: [(CH3)3SiNCO]2, Mr = 230.41, T = 100 K, monoclinic, I2/a, a = 20.257(2), b = 6.416(1), c = 21.260(3) Å, β = 101.29(1)°, V = 2709.7(6) Å3, Z = 8, dx = 1.130 g/cm3, μ = 2.4 cm−1, R = 4.86%, Rw = 4.39% (2375 observations, 151 parameters). In both compounds, the symmetry of the (XNCO)2 framework (X = Cl, Si) was determined to be nearly C2h with trans configuration of the exocyclic X atoms. Extreme values were observed for the angles between the ring plane and the exocyclic N–X bonds: 32.5(1)° in 1 and 2.5(2)° and 0.8(2)° in 2, respectively. Quantum chemical procedures at various levels of theory (ab initio SCF and semi‐empirical PM3) applied to 1 revealed the possible appearance of two isomers, a lower energy trans form and a higher energy cis form (approx. 2.4 kcal/mol above trans) differing mainly in the spatial arrangement of the chlorine atoms. The calculations excluded a planar heavy‐atom configuration by missing a local energy minimum.
Crystal structure of dicyclohexylammonium succinatotriphenylstannate at 138 K
Authors: Ng Seik Weng , Das V. G. Kumar , Xiao Gaoyi , Helm Dick Van Der , Holec̆ek Jaroslav , Lyc̆ka Antonín
Published: January 2005

Dicyclohexylammonium succinatotriphenylstannate, synthesized by condensing [(c‐C6H11)2NH2] [HO2C(CH2)2CO2] with (C6H5)3SnOH, has a zig‐zag structure consisting of polymeric chains in which planar triphenyltin cations (Σ C–Sn–C = 360.0(2)°) are axially linked by succinato dianions (Sn–O = 2.214(2) Å; O–Sn–O = 172.52(6)°); the dicyclohexylammonium cations surround the chain and are hydrogen‐bonded to the acyl oxygens of the ligand (N…O = 2.829(3) Å). The stannate is four‐coordinate in CDCl3 solution.
2,4‐Dimethoxycarbonyl‐1,1,3,3‐tetrakis(dimethylamino)‐1λ5,3λ5‐diphosphete
Authors: Fluck Ekkehard , Spahn Manfred , Heckmann Gernot , Borrmann Horst , Obermeyer Axel
Published: January 2005

1,1,3,3 ‐ Tetrakis(dimethylamino) ‐ 1λ5,3λ5 ‐ diphosphete, 1, reacts with cyanoformic acid methyl ester to form two isomers of the title compound 2. Properties, NMR, mass, and IR spectra of 2, as well as the molecular and crystal structure of the E isomer of 2, are described and discussed.
Enolization of the phosphoryl group
Authors: Mastryukova Tatjana A. , Kabachnik Martin I.
Published: January 2005

Enolization of the phosphoryl group has been studied where Y = PPh3, CN, Ts, COOEt, CONEt2; R and R′ = Et, Bu, Ph, EtO, BuO, PhO; and X = Cl, Br, ClO4, BF4. It has been established that substances with are phosphaenols, but in substances with Y = CONEt2 the phosphoryl group cannot be enolized under any conditions. Phosphaenolization is favored by a high acidifying ability of the Y group, the ability of the X anion to stabilize the phosphaenolic form due to formation of a hydrogen bond OH…X with the anion, and a low electronegativity of R and R′ groups. To evaluate the acidifying ability of Y, this article defines specific σ− constants dependent on the number of substituents at the α‐carbon atom: σCH3−, σCH2− and σCH−. Their sums characterize the enolization ability of the phosphoryl group. The enolic structure in the solid state is possible if ∑CHn− > 2. If this sum lies in the range of 2 < ∑CHn− < 2.6 the phosphoryl–phosphaenol tautomerism can be expected in appropriate solutions. Acidic properties of the investigated compounds in MeNO2 and EtOH (absolute) have been determined. Calculations of the acidity of the phosphoryl CH forms (A) and of the phosphaenol OH forms (B) have been carried out.
Crystal structure and stereochemistry of (PS*, 2S*, 3aS*)‐hexahydro‐2‐(tert‐butylvinylthiophosphinyl)‐6,6‐ dimethylpyrrolo[1,2‐b]isoxazole
Authors: Pietrusiewicz K. Michał , Wieczorek Wanda , Cicchi Stefano , Brandi Alberto
Published: January 2005

The structure of the major product of the cycloaddition of 2,2‐dimethyl‐3,4‐dihydro‐2H‐pyrrole N‐oxide to tert‐butyldivinylphosphine sulfide was analyzed by means of single‐crystal X‐ray diffraction technique. The analysis revealed two crystallographically independent molecules that differed in conformation of the fused five‐membered heterocyclic rings. These rings were found to be two envelopes in one molecule and two half‐chairs in the other. The studied compound was identified as an exo adduct of the expected erythro configuration and was found to favor a conformation in which the PS and ring C–O bonds were anti and the CC–PS moiety was in the s‐cis array. C14H26NOPS, space group P¯1, a = 10.6004(7) Å, b = 12.3225(6) Å, c = 13.4404(7) Å, α = 104.073(4)°, β = 92.758(4)°, γ = 95.968(5)°, V = 1688.802(4) Å3, Z = 4.
Dense compounds of C, H, N, and O atoms: II [1]. Nitramine and nitrosamine derivatives of 2‐oxo‐ and 2‐iminooctahydroimidazo‐[4,5‐d]imidazole
Authors: Ramakrishnan Vayalakkavoor T. , Vedachalam Murugappa , Boyer Joseph H.
Published: January 2005

The 4,6‐dinitroso derivative 11 was obtained (83%) by the nitrosation of 2‐oxooctahydroimidazo[4,5‐d]‐imidazole 1 as the dihydrochloride and was converted to the 4,6‐dinitro derivative 12 [66%] by treatment with nitric acid (100%, ‐40°C) and to the 1,4,6‐trinitro derivative 13 (66%) and the 1,3,4,6‐tetranitro derivative 2 (86%) by treatment with nitric acid (100%) in acetic anhydride at 0–5°C and 10–25°C respectively. Similar treatment with nitric acid (100%) in either acetic or trifluoroacetic anhydride at 0–25°C converted the trinitro compound 13 to the tetranitro compound 2 (86%). The dinitramine 12 was also obtained (43%) from the diamine 1 by nitration with nitric acid (100%, ‐40°C). A reaction between 2‐nitrimino‐5‐iminooctahydroimidazo[4,5‐d]imidazole 7 as a hydrochloride salt (from an acid catalyzed condensation between 4,5‐dihydroxy‐2‐nitriminoimidazolidine 6 and guanidine) and nitric acid (100%, ‐40°C) gave the 2,5‐dinitrimino derivative 14 (85%) isolated as a monohydrate. The nitrate salt 7 · HNO3, isomeric with 14 · H2O, was obtained from the corresponding hydrochloride 7 · HCl and silver nitrate. Both nitrimines 7 and 14 gave 1,3,4,6‐tetranitro‐2,5‐dioxooctahydroimidazo[4,5‐d]imidazole 15 (66% and 59%) by treatment with nitric acid (100%) in acetic anhydride.
Ground state conformation of diphenylvinylphosphine sulfide and selenide
Authors: Pietrusiewicz K. Michał , Kuźnikowski Maciej , Wieczorek Wanda , Brandi Alberto
Published: January 2005

Single‐crystal X‐ray diffraction experiments have been performed on diphenylvinylphosphine sulfide (1): C14H13PS, space group P21/c, a = 10.186(1) Ǎ, b = 11.918(1) Å, c = 11.426 Å, β = 112.22(2)°, V = 1284.1(2) Å3, Z = 4, and diphenylvinylphosphine selenide (2): C14H13PSe, space group Pbca, a = 9.141 (3) Å, b = 16.458 (1) Å, c = 17.451 (1) Å, V = 2625.4 (9) Å3, Z = 8. The structures were solved by direct methods and were refined by full matrix least‐squares calculations to R = 0.046 and Rw = 0.058 using 2554 unique reflections with I > 3σ(I) in the case of 1, and to R = 0.052 and Rw = 0.065 using 1953 unique reflections with I > 3σ(I) in the case of 2. In close analogy to the previously studied vinyl phosphine oxides both 1 and 2 were found to exist in the s‐cis conformation with the pertinent CCPX dihedral angles equal to 12.5° and 2.9° for 1 and 2, respectively.
Oxygen‐17 nuclear magnetic resonance spectroscopy of organosulfur compounds. Part III. 17O NMR lanthanide‐induced shifts (LIS) of diastereotopic oxygen atoms in trans‐2‐ [alkyl(aryl)sulfonyl]cyclohexanols
Authors: Powers Thomas A. , Evans Slayton A.
Published: January 2005

The 17O NMR diastereotopicity or chemical shift differences of diastereotopic sulfonyl oxygens in a series of trans‐2‐[alkyl(aryl)sulfonyl]cyclohexanols have been determined. From a comparison of their sulfonyl oxygen 17O NMR lanthanide‐induced shifts, equilibrium distributions between diastereomeric sulfonyl oxygen‐Eu(fod)3 complexes were determined and found to be sensitive to both the steric size of the –SO2R substituent as well as the proximity of the C1 hydroxyl group.
Conformationally controlled intramolecular heterocyclization of 2,4‐diaminoperfluoro‐4‐methyl‐2‐pentenethiocyanate‐3
Authors: Popkova Vera Ya. , Antipin Mikhail Yu. , Vinogradova Lyudmila E. , Leites Larisa A. , Struchkov Yuri T.
Published: January 2005

Perfluoro‐2‐methyl‐2‐pentene‐thiocyanate‐3 reacts with ammonia to give 2,4‐diaminoperfluoro‐4‐methyl‐2‐pentenethiocyanate‐3 (4) and 2‐aminoperfluoro‐4, 4‐dimethyl‐4,5‐dihydro‐5‐ethylidene‐1,3‐thiazole (5). Compound 4 is kinetically stable and at 150°C under‐goes rotational isomerization to afford the cyclic isomer 2‐amino‐4,4‐bis(trifluoromethyl)‐4,5‐dihydro‐5‐(1‐aminoperfluoroethylidene) ‐1,3‐thiazole (6). Intramolecular cyclizations, resulting in the thiazolines 5 and 6, proceed likewise via the Thorpe reaction. For compounds 4–6, X‐ray diffraction analyses were undertaken and IR spectra in solution and in solid state were investigated. It is supposed that a high kinetic preference for formation of 4 and the fact that it does not undergo spontaneous cyclization in ammonolysis stem from the NH …︁ N intramolecular hydrogen bonding between two amino groups.
Synthesis of N,P,S,Se‐containing mono‐ and bicyclic compounds in reactions of isothiocyanato‐ and diisothiocyanato(di)chloromethyl(thio) phosphonates with hydrosulfur(seleno) compounds
Authors: Kamalov R. M. , Stepanov G. S. , Chertanova L. F. , Gazikasheva A. A. , Pudovik M. A. , Pudovik A. N.
Published: January 2005

Reactions of phenyl isothiocyanato(di)chloro‐methyl(thio)phosphonates (1) with thiols in the presence of a base give rise to 2‐alkylthio‐4,5‐dihydro‐4‐oxo(thioxo)‐4‐phenoxy‐1,3,4‐thiazaphospholes (5). Some of these compounds can also be obtained by alkylation of 2,4‐dithioxo‐4‐phenoxy‐1,3,4‐thiazaphospholidine (4), which is formed in the reaction of phenyl isothiocyanatochloromethylthiophosphonate (1a) with sodium hydrosulfide. The interaction of 1a with H2Se and triethylamine results in the formation of 2,4‐dithioxo‐4‐phenoxy‐1,3,4‐selenazaphospholidine (8), which when alkylated affords 2‐alkylthio‐4,5‐dihydro‐4‐phenoxy‐4‐thioxo‐1,3,4‐selenazaphospholes (9) Diisothiocyanatodichloromethyl(thio)‐phosphonates (11) react with α‐toluenethiol in the presence of a base, giving rise to 3,7‐bis(benzylthio)‐1‐oxo(thioxo)bicyclo[3.3.0]‐4,6‐dithia‐2,8‐diaza‐1‐phosphocta‐2, 7‐dienes (13). By the interaction of phenyl isothiocyanatotrichlorome‐thylthiophosphonate (14) with ethanethiol and Et3N, S‐ethyl‐N‐(O‐phenyl(trichloromethyl)thiophosphonyl)dithiocarbamate triethylammonium salt (15) has been formed. The molecular structures of some P,N,S,Se‐containing heterocycles that we have synthesized have been studied by X‐ray diffraction.
Wittig reaction of 1‐dicyanomethyleneacenaphthen‐2‐one
Authors: Abdou Wafaa M. , Ganoub Neven A. F.
Published: January 2005

The Wittig reaction of the titled compound 2 with alkoxycarbonylmethylenetriphenylphosphoranes (1a,b) has been investigated and the reaction products 6, 10, and 11 isolated and identified. On the other hand, reaction of 2 with benzoylmethylenetriphenyl‐phosphorane (1c) proceeded only at high temperature, yielding 7c and 10. Mechanisms accounting for the formation of the adducts are discussed, and the synthetic utility of the products were tested.
Reactions of tellurium(IV) chloride, aryl‐, diaryl‐, and triaryl tellurium(IV) chlorides with pyrimidine‐2‐thiols
Authors: Singh Ajai K. , Singh Veena , Khandelwal Bishan L.
Published: January 2005

1‐Substituted 4,4,6‐trimethyl‐1H, 4H‐pyrimidine‐2‐thiol(L), whose substituents are C6H5 (1), p‐CH3OC6H4 (2), p‐O2NC6H4 (3), n‐C4H9 (4), and NH2 (5), react with TeCl4, ArTeCl3 (Ar = C6H5, 4‐CH3OC6H4, or 4‐C2H5OC6H4), Ph2TeCl2, and Ph3TeCl, resulting in TeCl3(L–H), ArTeCl2(L–H), Ph2TeCl2.L, and Ph3TeCl.L types of compounds. Elemental analyses, molecular weights, conductances in solutions, IR, and 1H and 13C NMR spectral data of these compounds suggest that, in all of them, the pyrimidine‐2‐thiols ligate through sulfur only. In the first two types of derivatives, the thiol form of L reacts with tellurium moieties, resulting in the liberation of HCl. On the basis of these data TeCl3(L‐H) appears to exist as a dimer in which two Te atoms are probably 5‐coordinated and are bridged by two Cl. Tellurium in ArTeCl2(L‐H), Ph2TeCl2.L, and Ph3TeCl.L also appears to be 5‐coordinated. IR data suggest that the Te–S bond in Ph2TeCl2.L is weak and, therefore, because of partial dissociation, the molecular complexes exhibit lower molecular weights in CH3CN. Ph3TeCl.L in acetonitrile behaves as a 1:1 electrolyte. Attempts to synthesize N‐, S‐, and Te‐containing heterocycle ring compounds from TeCl3(1/2‐H) and ArTe(1/2‐H)Cl2 did not succeed.
A 1,5‐diaza‐2,4‐(λ4P+, λ6P−)‐diphosphorinane
Authors: Shevchenko Igor V. , Jones Peter G. , Fischer Axel , Schmutzler Reinhard
Published: January 2005

The oxidation of the 1,3‐diaza‐4,6‐diphosphorine 1 with tetrachloroorthobenzoquinone 2 led, unexpectedly, to the formation of 1,5‐dimethyl‐2,2‐bis(dimethyl‐amino)‐4,4,4,4‐bis‐(tetrachloro‐o‐phenylenedioxa)‐1,5‐diaza‐2,4‐λ4, λ6‐diphosphorinane‐6‐one 4, containing two phosphorus atoms of opposite formal charge and different coordination number. The X‐ray crystal structure analysis of 4 revealed the presence of a six‐membered ring with an unusual conformation.
Preparations and reactions of trifluoromethylthiocopper
Authors: Munavalli Shekar , Rossman David I. , Rohrbaugh Dennis K. , Ferguson C. Parker , Hsu Fu‐Lian
Published: January 2005

Trifluoromethylthiocopper, a versatile reagent for the introduction of the trifluoromethylthio group into organic compounds, has been prepared in a crystalline form. The thiyl radicals, generated in situ from this precursor, cause the cleavage of the 3S bond of di‐ and trisulfides to give unsymmetrical di‐ and trisulfides. Unsymmeirical n‐butyl trifluoromethyl disulfide is formed by the cleaveage of the CS bond of n‐butyl sulfide.
Reactions of β‐nitrostyrenes with tert‐butylmercury halides in the presence of lodide lon
Authors: Russell Glen A. , Yao Ching‐Fa
Published: January 2005

Photolysis of t‐BuHgCl/KI with PhC(R2)C(R1)NO2 forms PhC(R2)C(R1)Bu‐t when R1 = R2 = H or in low yield when R1 = H, R2 = Ph. When R1 ≠ H, or when R2 = Ph, reactions with t‐BuHgI/KI/hv proceed mainly via PhC(R2)C(R1)NO2·‐, PhC(R2)C(R1)N(OBu‐t)O−HgX+, PhC(R2)C(R1)NO and PhC(R2)C(R1)N(OBu‐t)HgX to form a variety of novel products including the dimeric bisnitronic esters (6) with R1 = Me or Ph and R2 = H; PhCH(R2)C(R1) = NOBu‐t with R1 = Me or Ph and R2 = H or R1 = H and R2 = Ph; PhC(R2)(OBu‐t)C(R1)NOH with R1 = H or Me and R2 = Ph; and 3‐phenyl‐2‐R1‐indoles with R1 = H, Me, Ph, PhS or t‐BuS and R2 = Ph. Nitrosoaromatics react with t‐BuHgX in the dark to form ArN(OBu‐t)(OBu‐t)HgX+ which condenses with ArNO to form the azoxy compound. tert‐Butyl radicals will add to RNO2 [R = Ph, Ph2CCH, Ph2CC(Ph)] in the presence of t‐BuHgI2− to form products derived from RN(OBu‐t)O−HgI+.
The correlation of 11B NMR ASIS effects with MO‐derived charge densities for closo‐C2B5H7 and some chloro derivatives
Authors: Onak Thomas , Abdou Zahid J. , Abdou Gaby , Herrera Sergio
Published: January 2005

Aromatic‐solvent‐induced 11B NMR shifts (11B ASIS effects), observed for closo‐2, 4‐C2B5H7 and its 5‐chloro and 5, 6‐dichloro derivatives, are correlated to ab initio STO‐3G derived atom charge densities. A near linear relationship is found upon incorporating nearestneighbor charge density contributions.
Structure and derivatization of the product from carbonylation of lithium triethylborohydride
Authors: Hubbard John L.
Published: January 2005

Treatment of the reactive product from carbonylation of lithium triethylborohydride with the electrophilic reagent chlorotrimethylsilane does not produce the expected α‐hydroxyborane derivative. Instead, a borinate arising through migration of a second ethyl group from boron to carbon is obtained. This result is rationalized in terms of the initial product being a borate having two possible constitutions. The borate nature of this initial product is confirmed by 11B NMR.
Solid state 13C NMR can distinguish between bronsted and Lewis acid adducts of amines
Authors: Ofori‐Okai Gabriel , Bank Shelton
Published: January 2005

The solid 13C NMR spectra of solid complexes of phenethylamine with SnCl4, Me3SnCl, AlCl3, and HCl are presented and discussed as a means of distinguishing between Bronsted and Lewis acid adducts of alkyl amines. Solution 13C NMR results are discussed in terms of species present in complex equilibria and their detection using the two NMR methods.
Synthesis and reactions of 2,2,2‐trihaloethyl α‐hydroxyiminobenzylphosphonates. The influence of the ester group on the chemistry of phosphonates
Authors: Breuer Eli , Mahajna Mahmoud
Published: January 2005

Arbuzov reactions of diethyl 2,2,2‐trihaloethyl phosphites (3) with benzoyl chloride afforded ethyl 2,2,2‐trihaloethyl benzoylphosphonates (4). The reactions of 4 with NH2OH.HCl led to the formation of methyl benzoate and ethyl methyl H‐phosphonate as a result of alcoholysis of 4, followed by alkoxy group exchange. Methanol solutions of benzoylphosphonates 4 were found by 31P NMR spectroscopy to contain considerable proportions of hemiacetals, 7, which undergo base‐catalyzed CP bond cleavage. The formation of hemiacetals from benzoylphosphonates 4 is suppressed in 2‐propanol, and in this solvent the corresponding oximes 2 could be obtained in good yields. Reactions of methyl benzoylphosphonochloridate (10) with 2,2,2‐trihaloethanols, in CH2Cl2, gave methyl 2,2,2‐trihaloethyl benzoylphosphonates (11) which could be converted directly to oximes 12 by NH2OH.HCl in a one‐pot procedure. In contrast to the previously studied dimethyl (E)‐α‐hydroxyiminobenzylphosphonate, which underwent thermal Beckmann rearrangement to afford N‐benzoylphosphoramidates, both (E) and (Z)‐trihaloethyl esters 2 and 12 underwent fragmentation to benzonitrile and to the corresponding dialkyl hydrogen phosphate, reflecting the increased electrophilicity of the phosphorus in these compounds. Demethylation of methyl esters 12 was effected smoothly by iodide or bromide ions to yield benzoylphosphonate salts 15, which in turn were converted to oxime salts 14 by treatment with hydroxylamine. In contrast, attempted deethylation of ethylesters 2 in refluxing acetonitrile led to benzonitrile and pyrophosphate type product as indicated by 31P spectroscopic examination of the reaction mixture. Oxime salts 14 behaved similarly when heated. Acidification of lithium 2,2,2‐trifluoroethyl α‐hydroxyiminobenzylphosphonate (14a) gave the corresponding hydrogen trifluoroethyl phosphonate (19a). The fragmentation of 19a in 0.6 N ethanolic hydrogen chloride to ethyl trifluoroethyl hydrogen phosphate and benzonitrile at room temperature had a T1/2 value of approx 18 hours, which is greater by a factor of 2 than that of the corresponding methyl ester. When the fragmentation of 19 was carried out in solvent mixtures of either water with methanol or 2‐propanol, or methanol with tbutanol, the composition of the solvents was reflected in the products, indicating a dissociative type mechanism, involving metaphosphate as reactive intermediates.
Preparation of α,α‐difluoromethylene functionalized sulfones
Authors: Yang Zhen‐Yu , Burton Donald J.
Published: January 2005

Sulfination of bromodifluoroacetate or acetamide 1 with sodium dithionite gives the corresponding sulfinates 2a, and 2b, respectively, which upon cuprous bromidc catalyzed allylation afford the allylsulfonyl‐difluoroacetate and acetamides. Phenyl‐ or alkylsulfonyldifluoroacetates and acetamides can be readily prepared from reaction of 1 with thiolates, followed by oxidation with hydrogen peroxide.
A novel method for the preparation of diborane from aluminum, ethyl chloride, boron oxide and hydrogen
Authors: Zhao Chengwen , Gu Yijian , Rui Zunhong , Lin Zhongqiang , Yin Huoming , Lu Guangyu , Tao Yusheng
Published: January 2005

A novel method is described for the preparation of diborane from aluminum, ethyl chloride, boron oxide and hydrogen via three steps; deoxyalkylation of boron oxide, hydrogenation of triethylboron and liberation of diborane. The triethylboron was prepared from aluminum, ethyl chloride and boron oxide directly at 85–110°C in 88% yield, with aluminum trichloride as by‐product in 95% yield. In the presence of triethylamine and a hydrogen pressure of 130 kg/cm2, the triethylboron was hydrogenated at 200°C for 2 hours to produce borane‐triethylamine complex in 92% yield. The borane‐triethylamine complex was treated again at 80°C with the aluminum trichloride collected from the first step to liberate diborane in 94% yield. The overall reaction yield was 76%.
The preparation and reactions of protected glyphosate imidate, thioimidate, and thiono esters from N‐[diphenoxyphosphinylmethyl]glycinonitrile: Comparative reactivities of activated carboxylate versus phosphonate esters
Authors: Dutra Gerard A. , Finkes Michael J. , Sikorski James A.
Published: January 2005

The highly efficient syntheses of novel protected glyphosate imidate, thioimidate, and thiono ester derivatives are described starting from N‐[diphenoxyphosphinylmethyl]glycinonitrile 3b. The scope, utility and limitations in using each of these activated carboxylate functionalities for further transformations to new “masked” heterocyclic derivatives are defined. While the solution stability of the imidate and thioimidate series limited the synthetic application of these species, the corresponding thiono ester derivatives were valuable synthetic intermediates, providing a short, efficient route to the first glyphosate derivatives containing 1,3,4‐oxadiazole and 1,2,4‐triazole ring systems in place of the carboxylate group. These thiono esters thus undergo selective nucleophilic addition at this activated carboxylate center, while retaining the reactive diphenyl phosphonate moiety.
Interaction of molecular SiS with silver atoms in an argon matrix: IR spectrum and ab initio rationalization
Authors: Köppe Ralf , Schnöckel Hansgeorg , Jouany Claude , Gadea Florent Xavier , Barthelat Jean Claude
Published: January 2005

Co‐condensation of silver atoms and SiS in an argon matrix leads to the formation of Ag(SiS). The IR spectrum can be interpreted in two different ways: Isotopic shifts (28Si/29Si, 28Si/30Si, 32S/34S) imply a side‐on coordination of SiS to silver. On the other hand, the SiS frequency and the isotopic shifts can be assigned to an isolated SiS− molecule. The SiS force constant is reduced from 5.0 mdyn/Å in free SiS to 3.9 mdyn/Å in AgSiS. Ab initio investigations confirm the formation of an ion pair Ag+(SiS)−, admitting some electron delocalization.
1, 1‐dichloroalkylphosphonates: Convenient starting materials for low‐coordinated trivalent phosphorus compounds
Authors: Grandin Catherine , About‐Jaudet Elie , Collignon Noël , Denis Jean‐Marc , Savignac Philippe
Published: January 2005

Diisopropyl 1,1‐dichloroalkylphosphonates bearing various groups (alkyl, aryl, allyl, benzyl, phenylthiolate, trimethylsilyl) in the α‐position were reduced to the corresponding primary 1,1‐dichlorophosphines by the LiAlH4‐AlCl3 system in diethyl ether. Subsequent dehydrochlorination with tertiary amines in the presence of trapping dipolar compounds (ethyl diazoacetate or n‐hexylazide) led to the expected 1,2,4‐diazaphospholes or 3H‐1,2,3,4‐triazaphospholes.
4‐Halogeno‐3‐oxides and sulfides of the 3,4‐dihydro‐2h‐1,2,3‐diazaphosphole system
Authors: Baccolini Graziano , Dalpozzo Renato , Todesco Paolo E.
Published: January 2005

4‐Bromodiazaphosphole‐3‐oxides or sulfides can be obtained by reaction of the corresponding unsubstituted derivative with appropriate reagents. PTAB was demonstrated to be very regio‐ and stereoselective, allowing bromination exclusively at the 4‐position of the ring with prevalent or exclusive formation of one of the two possible isomers. However, when regioselectivity is not required, cheaper and more available bromine or NBS can be used conveniently. 4‐Chlorodiazaphosphole‐3‐oxides can be obtained by reaction of the corresponding unsubstituted derivative with NCS. 4‐Bromodiazaphosphole‐3‐oxides undergo stereoselective methanolysis as well as parent unsubstituted oxides.
1, 3‐azaphospholo[5, 1‐b]thiazolines and benzothiazoles
Authors: Bansal Raj K. , Mahnot Ruchi , Sharma Dinesh C. , Karaghiosoff Konstantin , Schmidpeter Alfred
Published: January 2005

The title compounds 3 and 7 are novel heterocyclic systems incorporating two‐coordinate phosphorus. They are obtained in reasonable to good yields from the condensation of suitable 2‐ethyl‐3‐alkylthiazolinium and ‐benzothiazolium bromides 2 and 6 with phosphorus trichloride in the presence of triethylamine in an aprotic solvent. Intermediate dichlorophosphino‐substituted N‐ylides can be observed or isolated in some cases. From a 2‐methyl‐3‐alkylthiazolinium bromide (2a), a 1‐(dichlorophosphino) substituted 1, 3‐azaphospholo[5,1‐b]thiazoline (4) was obtained.

The chemical shift of the two‐coordinate phosphorus in 1,3‐azaphosphole derivatives clearly reflects the influence of the heterocyclic system annulated to its 1,5‐bond and of the substituents in its 2‐and 4‐positions.
The properties of thiobenzyl esters of the P(III) acids. Part I. The study of the reaction mechanism of 2‐benzylthio‐4,5‐benzo‐1,3,2‐dioxaphospholane with ketones and oxygen by CIDNP 31P
Authors: Drozdova Yana A. , Burilov Alexander R. , Pudovik Michael A. , Gainullin Rafinad M. , Il'Yasov Akhat V.
Published: January 2005

2‐Benzylthio‐4,5‐benzo‐1,3,2‐dioxaphospholane reacts with oxygen to form the corresponding thiophosphonate, dithiophosphate and pyrophosphite. The reaction was found to be of a radical nature. The mechanism is suggested to involve an initial electron transfer with suitable subsequent transformations. The interaction of the title compound with various ketones in a pure oxygen atmosphere was studied by the CIDNP method.
A new synthesis of unsymmetrically substituted halophosphines
Authors: Omelańczuk Jan
Published: January 2005

Chiral, racemic alkylaryl‐, or diarylhalophosphines have been obtained in 50–70% yields by treatment of alkylaryl‐ or diaryl‐methylthiohalophosphonium triflates with triphenylphosphine in methylene chloride solution at room temperature or under reflux.
Aminomethylphosphines in template synthesis on Pt(II), Pd(II), and Hg(II)
Authors: Nikonov G. N. , Karasik A. A. , Malova E. V. , Enikeev K. M.
Published: January 2005

Reactions of 5‐p‐toluidinomethyl‐1,3‐ditolyl‐1,3,5‐diazaphosphorinane 1 with Pt(II), Pd(II), Hg(II) salts are reported. Complex formation was followed by template synthesis of novel bicyclic ligand and chelate complexes. Compounds 2, 3, 4 have been formed. The mercury complex 4 was also obtained in high yield by electrochemical oxidation of compound 1 at the Hg‐anode. Conformational features of new ligands are discussed on the basis of NMR data.
An efficient synthesis of phosphenimidous esters, ROPNAr
Authors: Romanenko Vadim D. , Reitel Grigorii V. , Chernega Alexander N. , Kirichenko Oleg V. , Ruban Alexander V. , Sanchez Michel , Wolf Robert , Mazières M. R.
Published: January 2005

Trimethylsilyltrifluoromethane sulfonate is shown to be an efficient catalyst for the elimination of Me3SiCl from N‐trimethylsilyl‐N‐(2,4,6‐tri‐tert‐butylphenyl)amidochlorophosphites la‐f, leading to the phosphenimidous esters 3a–f. The crystal structures of phosphites 1a and 1d provide a stereochemical explanation for the better thermal stability of 1d On the basis of these observations a convenient and general synthesis of phosphenimidous esters 3a–f is presented.
A new method for construction of cyclic enones via phosphonate anions
Authors: Furuta Toshiaki , Oshima Eriko , Yamamoto Yoshinori
Published: January 2005

The reaction of 2,2‐disubstituted 1,3‐cyclohexane‐diones (1) with dimethyl methylphosphonate anion in the presence of trimethylsilyl chloride produces 3‐substituted 2‐cyclohexenones (2) in moderate to very good yields. This new overall reaction is accounted for by (1) attack of the phosphonate anion on a carbonyl group, (2) retro‐aldol cleavage, (3) reorganization of the acidic proton, and (4) an intramolecular Wadsworth‐Emmonds condensation. The new rearrangement is applied to a short synthesis of (±)‐α‐acoradiene. The synthesis of 3‐sub‐stituted 2‐cyclopentenones (10) is accomplished via two‐step processes.
Study on the α‐sulfenylation of 3‐sulfolenes
Authors: Chou Ta‐shue , Chang Sheng‐Yueh
Published: January 2005

The reactions of 3‐sulfolenes with PhSCl under basic‐conditions produce phenyl 1,3‐butadienethiosulfonates 7a–d in low yields without the formation of 2‐sulfenylated 3‐sulfolenes 8. Compounds 7a–d can be prepared in high yields from 3‐sulfolenes by the sequence of deprotonation, anionic cycloreversion, and phenylsulfenylation reactions.
A selective synthesis of 3‐alkynl perflouroalkyl ketones by the trifluoroborane etherate mediated 1,4‐addition reaction of (1‐alkynyl)diisopropoxyboranes to α,β‐unsaturated ketones
Authors: Takada Ei‐ichi , Hara Shoji , Suzuki Akira
Published: January 2005

A variety of 3‐alkynyl perfluoroalkyl ketones were prepared by a trifluoroborane etherate mediated 1,4‐addition reaction of (l‐alkynyl)diisopropoxyboranes to α,β‐unsaturated ketones substituted by a perfluoroalkyl group. The undesired side reaction, such as 1,2‐addition of alkynyl groups, could be avoided completely and the products were obtained in high yields.
Further evidence to understand the stereochemistry of the reactions of α‐sulfinyl carbanions
Authors: Ohno Atsuyoshi , Higaki Masato , Okamura Mutsuo
Published: January 2005

The stereochemistry of the α‐sulfinyl carbanion has been studied. It has been elucidated that a 2‐pyridylmethyl substituent on the sulfinyl sulfur chelates onto the counter cation in an ion pair to fix the conformation of the anion at a particular orientation. Then, the steric bulk of the other substituent plays a role to control the reacting face. A soft electrophile such as methyl iodide attacks the anion from the more open side. On the other hand, a hard electrophile such as a proton is initially trapped by the polar part of the ion pair and no steric effect operates.
Effect of phosphorus ligands on the hydroformylation of olefins over rhodium catalysts under atmospheric pressure
Authors: Chen Wanzhi , Liao Shijian , Xu Yun
Published: January 2005

The hydroformylation of olefins over rhodium catalysts, with phosphorus ligands added in situ, has been studied under atmospheric pressure. In the case of the Rh4(CO)12 cluster, the phosphine‐modified catalyst exhibits very high activity, but there is a decay of catalyst activity with time. The deactivation mechanism of this catalyst has been discussed. In the case of rhodium complexes, Rh(LL′)(CO)2, containing chelate ligands with oxygen and nitrogen as coordinate atoms, the phosphine‐modified catalysts exhibit fairly active activity and very good stability. All these catalysts afford almost 100% chemoselectivity to aldehydes. The regioselectivity is strongly dependent on the nature of the substrate used. The choice of a suitable phosphorus ligand for the catalytic hydrofor‐mylation is dependent on the nature of the rhodium complex used. The effect of phosphorus ligands on the hydroformylation of olefins over rhodium catalysts under normal pressure displays some special features in comparison with that performed under a higher pressure.
Synthesis of trimethylsily enynyl carboxylates via a silylated arsonium ylide
Authors: Shen Yanchang , Xiang Yuejun
Published: January 2005

Silylated enynyl carboxylic esters can be synthesized with high stereoselectivity by the reaction of 3‐trimethylsilyl 2‐propynylidenetriphenylarsorane, generated in situ from the corresponding arsoniunm salt with n‐butyllithium and α‐bromoacetic esters.
Umpolung reactivity of allylic phosphonates. A simple route to 3‐aminoalkane‐ and 3‐amino‐1‐alkenylphosphonates (phosphinates and phosphine oxides)
Authors: Lu Xiyan , Sun Junhui , Zhu Jingyang
Published: January 2005

Dibutyl allylphosphonate can react with palladium chloride to give the dibutyl phosphorylated π‐allylpalladium chloride complex which was found to be able to react with a nucleophile, such as sodium dimethyl malonate, to give a functionalized 1‐alkenyl‐phosphonate. A 1‐acetoxyallylic phosphonate can be regarded as the precursor of a phosphorylated π‐allylic palladium complex in a palladium(O) catalyzed reaction, and the latter reacts with nucleophiles to yield 3‐substituted I‐alkenylphosphonates. The reaction is regioselective. Using this methodology, 3‐aminoalkane‐ and 3‐aminoalkenylphosphonates were synthesized from 1‐acetoxyallylic phosphonates regioselectively.
Hypervalent iodine in synthesis: 13: Action of phenyliodine(III) dicarboxylates on diaryltellurides: A facile and general method for the preparation of diaryltellurium dicarboxylates
Authors: Liu Zu‐Dong , Chen Zhen‐Chu
Published: January 2005

A facile and general method for the preparation of diaryltellurium dicarboxylates is described. The method involves simply the stirring of phenyliodine(III) dicarboxylates with diaryltellurides in chloroform at room temperature.
Studies on organosilicon reactive intermediates. VI. Photolysis of trisilanes containing heterocycles
Authors: Wu Shi‐Hui , Qian Hu , Wu Ge , Jiang Nan
Published: January 2005

Both 2‐phenyl‐2‐furylhexamethyltrisilane (1) and 2‐phenyl‐2‐thienylhexamethyltrisilane (2) were synthesized by conventional organometallic reactions. The photolysis of 1 in the presence of 2,3‐dimethyl‐1,3‐butadiene led to normal silylene‐olefin addition and silylene CH insertion reactions. However, when 2 was photolyzed in a methanol‐cyclohexene system, an apparent radical reaction occurred. We suspect that the sulfur atom of the thienyl group strongly stabilizes a silyl radical. This result was supported by both identifying its typical radical reaction products and examining the ESR spectrum of its adduct with a radical trap.
Sulfenylation reactions with disulfides in the presence of CCl4/base+
Authors: Hesselbarth Frank , Wenschuh Eberhard
Published: January 2005

Sulfenylation of active methylene compounds with disulfides and CCl4/base, proceeding in two steps, gives rise to more than 50% of the introduced sulfur component due to the reoxidation of the thiolate into the starting disulfide. Depending on the reaction conditions, arylacetonitriles and diaryl disulfides react to form mono‐ or bis‐sulfenylated products. By use of this method, a number of previously unknown α, α‐bis‐sulfenylated nitriles were prepared.
Studies on organophosphorus compounds 59. Regioselective phosphorylation and formylation of propenylphosphonates—A novel and convenient route to propenylidenebisphosphonates and 1‐methoxycarbonylpropenylphosphonates
Authors: Yuan Chengye , Li Chaozhong
Published: January 2005

Phosphorylation and formylation of 2‐(or 1‐)propenylphosphonates show high α‐regioselectivity and give, under different conditions, 2‐propenylidenebisphosphonates, 1‐methoxycarbonyl‐2‐propenylphosphonates, ethenylidebenebisphosphonates, and 1‐methoxycarbonylethenylphosphonates, respectively, in high yields.
Synthesis of triphenylphosphonium trichlorogermanate and analogs. Preparation of germylenes from triphenylphosphonium trichlorogermanate
Authors: Zhu Qinyan , Ford Kelley L. , Roskamp Eric J.
Published: January 2005

Triphenylphosphonium trichlorogermanate was prepared in quantitative yield by reducing germanium tetrachloride‐triphenylphosphine (1:1) with tributyl‐tin hydride in diethyl ether. Heating the phosphonium salt at 245°C gave Ph3P‐GeCl2 in 90% recrystallized yield. Treatment of the phosphonium salt with LiN(TMS)2 gave Ge[N(TMS)2]2 in 70–77% yield. Reaction of tin dichloride or zinc dichloride with triphenylphosphine and hydrogen chloride yielded tin and zinc analogs of triphenylphosphonium trichlorogermanate.
The synthesis of novel phosphonodipeptides and their herbicidal activity
Authors: Chen Ru‐Yu , Zhang Yue‐Hua , Chen Mu‐Ru
Published: January 2005

A series of novel phosphonodipeptides has been synthesized from diphenyl α‐aminoalkylphosphonates and N‐chloroacetyl‐N‐alkyl (or aryl)glycine ethyl esters. The structures of all the compounds prepared were proved by 1H NMR, IR, MS, and elemental analyses. The bioassay tests showed that some of the compound have good herbicidal activity.