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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 123 (1990), S. 691-696 
    ISSN: 0009-2940
    Keywords: Thioacetone, hexafluoro-/1,2,4-Dithiazolines/1,2,4-Thiaselenazolines ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New Syntheses of Trifluoromethyl-Substituted HeterocyclesDimeric hexafluorothioacetone (HFTA) (1) reacts with thiourea or phenylthiourea to give 1,2,4-dithiazolines 2a and 2b. Similarly, 1,2,4-thiaselenazoline 3 is obtained from the reaction of 1 with selenourea. Reaction of 1 with oxamic hydrazide or thiosemicarbazide leads to acyclic molecules 4 and 5. Besides 5, the cyclic isomer 6 is also observed in solution. The N-trifluoroacetyl derivative 6a is obtained from the reaction of 5 with trifluoracetic anhydride. The structures of 2b, 3, 5, and 6a have been determined by single-crystal X-ray crystallography.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0009-2940
    Keywords: Imido ligands ; Molybdenum complexes ; Tungsten complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Organometallic Imido Complexes - Higher Valent Derivatives of the d-Metal Acids, 1. - New Organometallic Imido Complexes of Molybdenum and Tungsten - Direct Introduction of the Cyclopentadienyl Group by Masking the High-Oxidation StateThe molybdenum(VI)bis(tert-butylimido) complex MO(NtBu)2-Cl2 is converted into the novel organomolybdenum(VI) derivative (η5-C5H5)MO(NtBu)2Cl (1) in excellent yield. The preparation of the pyridine complex W(NtBu)2Cl2py2 (2) provides a convenient starting material for an effective synthesis of the related complex (η5-C5H5)W(NtBu)2Cl (4).
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 0009-2940
    Keywords: Imido ligands ; Oxo ligands ; Pentamethylcyclopentadienyl ligand ; Molybdenum complexes ; Tungsten complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Organometallic Imido Complexes - Highervalent Derivatives of the d-Metal Acids, 3[4b]. - Synthesis and Reactions of Pentamethylcyclopentadienyl Imido Complexes of Molybdenum and Tungsten and an Efficient Strategy for the Synthesis of the Organometallates NBu4[Cp*MO3] (M = Mo, W)A convenient and new entry into the chemistry of highvalent pentamethylcyclopentadienyl halfsandwich complexes of molybdenum and tungsten is described. The reaction of Mo-(NtBu)2Cl2 or W(NtBu)2Cl2(py)2 with Cp*Li (Cp* = η5-C5Me5) provides a high-yield route to new complexes Cp*Mo-(NtBu)2Cl (1a) and Cp*W(NtBu)2Cl (1b) which are converted into a variety of diimido, monoimido, and oxo derivatives. Treatment of 1a,b with MeLi yields the highly volatile methyl derivatives Cp*Mo(NtBu)2Me (2a) and Cp*W(NtBu)2Me (2b), while protolysis of 1a,b with an excess of HCl gas leads to selective cleavage of only one imido function with formation of Cp*Mo(NtBu)Cl3 (3a) and Cp*W(NtBu)Cl3 (3b). In contrast, protolysis of 1a,b with aqueous HCl provides a high-yield route to the well-known organometallic oxides [Cp*MoO2]-(μ-O) (4a) and [Cp*WO2](μ-O) (4b). These two key compounds are easily converted into the organomolybdate and organotungstate salts NBu4[Cp*MoO3] (5a) and NBu4[Cp*WO3] (5b) by cleavage of the M-O-M bridge with NBu4[OH]. The X-ray structure of 3a is reported.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 0009-2940
    Keywords: Bis(cyclopentadienyl)methane ; Heterobimetallic complexes ; Imido complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The mononuclear rhodium complexes [(C5H5CH2C5H4)-Rh(CO)2] (1) and [(C5H5CH2C5H4)Rh(PhC≡CPh)(PiPr3)] (2) readily react with nBuLi or TlOEt to yield the corresponding lithium salts 3 and 4 or thallium salts 5 and 6. The reaction of these salts with [(C5H5)Nb(NtBu)Cl2] (7) leads to the formation of the heterodinuclear compounds [{CH2(C5H4)2}-{Rh(CO)2}{(C5H5)Nb(NtBu)Cl}] (8) and [{CH2(C5H4)2}-{Rh(PhC≡CPh)(PiPr3)}{(C5H5)Nb(NtBu)Cl}] (9), respectively. Treatment of 3-6 with [Mo(NtBu)2Cl2] (10) gives the heterodinuclear Rh/Mo complexes [{CH2(C5H4)2}{Rh(CO)2}-{Mo(NtBu)2Cl}] (11) and [{CH2(C5H4)2}{Rh(PhC≡CPh)-(PiPr3)}{Mo(NtBu)2Cl}] (12). The analogous reaction of [Mo(NMes)2Cl2(DME)] (13) with 3-6 yields the corresponding complexes [{CH2(C5H4)2}{Rh(CO)2}{Mo(NMes)2Cl}] (14) and [{CH2(C5H4)2}{Rh(PhC≡CPh)(PiPr3)}{Mo(NMes)2Cl}] (15). From the monometallated ligand [(C5H5CH2C5H4)M] (M = Li: 16; M = Tl: 17) and the imidometal compounds 7, 10 and 13, the mononuclear complexes [(C5H5CH2C5H4)(C5H5)Nb-(NtBu)Cl] (18) and [(C5H5CH2C5H4)Mo(NR)2Cl] (R = tBu: 19; R = Mes: 20) have been obtained.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 127 (1994), S. 1827-1835 
    ISSN: 0009-2940
    Keywords: Imido complexes, organometallic ; Molybdenum complexes ; Tungsten complexes ; Alkene complexes ; Alkyne complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Highervalent Derivatives of the d-Metal Acids, 14[1].  -  Diimido Complexes [M(NR)2(PMe3)2(L)] of Tetravalent Molybedenum and Tungsten: Structure, Molecular Dynamics, and Activation of π-Acidic Ligands[M(NMes)2Cl2(dme)] (M = Mo 1, W 2; Mes = mesityl) or the trans-phosphane complexes [M(NMes)2(PMe3)2Cl2] (3, 4) are reduced by C8K in the presence of PMe3 to give diamagnetic d2 complexes [Mo(NMes)2(PMe3}3] (5) and [W(NMes)2-(PMe3)3] (6). At least one PMe3 ligand in 5 and 6 is readily substituted by more π-acidic substrates such as ethene, ethyne, 2-butyne, and P(OEt)3. The reaction with ethene leads to [Mo(NMes)2(η2-C2H4)(PMe3)2] (7) and [W(NMes)2-(η2-C2H4)(PMe3)2] (8). Furthermore, pentacoordinate complexes [Mo(NMes)2(η2-C2Me2)(PMe3)2] (9), [W(NMes)2(η2-C2H2)(PMe3)2] (10), and [W(NMes)2(PMe3){P(OEt)3)2] (11) have been synthesized from 5 or 6. The X-ray structure analysis of 8 reveals a trigonal-bipyramidal geometry about tungsten with both arylimido groups perfectly lying in the equatorial mirror plane. The ethene ligand is occupying the third equatorial position. The C2 vector is oriented perpendicular to the WN2 plane. Dynamic NMR studies are consistent with a tbp geometry being also present in solution at the low-temperature limit. At higher temperatures a rapid exchange of the PMe3 ligands with noncoordinated phosphane according to a dissociative mechanism is observed.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 0009-2940
    Keywords: Hexafluorthioacetone / Thiazolines / Gold complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactions of 2.2,4,4-Tetrakis(trifluoromethyl)-1.3-dithietane phosphane Gold(1) Complex of a Thiazoline-4-thiolate with KNCS and KNCO - Crystal Structure of a Triphenyl-phosphane Gold(1) Complex of a Thiazoline-4-thiolate2,2,4,4-Tetrakis(trifluoromethyl)-1,3-dithietane (1) reacts with KNCS to yield the potassium salt of 4-mercapto-2,2,5,5-tetrakis(trifluoromethyl)-Δ3-thiazoline (2). An oxidative workup procedure results in the formation of the disulfide 6. The salt 2 reacts with methyl bromoacetate, benzyl bromide, 3-bromo-1-phenylpropene, and 1,3-diiodopropane to form the thioethers 3-5 and 7, respectively. Protonation of 2 results in the formation of the thiolactam 9. Disulfide 6 reacts with Cl2 in the presence of FeCl3 to yield the sulfenyl chloride 8. C-S bond formation (→10) is observed by treating 8 with Me3SiCN. The gold(I) complex 11 is formed from 2 and Ph3PAuCl. 11 crystallizes in the monoclinic space group P21/n and contains a linear P-Au-S unit. The reaction of 1 with KNCO leads after protonation to the perfluorinated lactam 12 and the cyanuric acid derivative 13.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 1517-1520 
    ISSN: 0009-2940
    Keywords: Diiminosuccinonitrile ; 2H-Imidazoles ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Chemistry of Cyanogen: Reactions of Diiminosuccinonitrile (DISN) with Sulfenyl Chlorides, Chlorotrimethylsilane and Ring Closure to Trifluoromethyl-Substituted 2H-Imidazoles4,5-Dicyano-2-hydroxy-2-(trifluoromethyl)-2H-imidazole (1) is easily prepared by treating DISN with trifluoroacetic anhydride. In the presence of 4-(dimethylamino)pyridine, however, the O-acylated derivative 2 is formed in excellent yield, while the reaction of 1 with chlorotrimethylsilane affords the O-silylated product 6. A bi-1,2,5-thiadiazole of the formula S2(CN)4Cl2 (5) is the final reaction product, when DISN is treated with sulfur dichloride in the presence of “naked” chloride ions. On the other hand the non-heterocyclic N-sulfenyl derivative 4 has readily been obtained, when DISN is treated with F3CSCl instead. Finally a procedure is described to convert DISN into the corresponding N-silylated diimine 3.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 2183-2186 
    ISSN: 0009-2940
    Keywords: Imido complexes ; Molybdenum complexes ; Tungsten complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Organometallic Imido Complexes - Highervalent Derivatives of the d-Metal Acids, 2[4]. - Alkyl-, Aryl-, and Cyclopentadienyl-Substituted Molybdenum(VI) and Tungsten(VI) Imido ComplexesCpMo(NtBu)2Cl (1a) and CpW(NtBu)2Cl (1b) (Cp = η5-C5H5) react with organolithium reagents to form alkyl and aryl complexes of the type CpMo(NtBu)2R 2a-4a and CpW(NtBu)2R 2b-4b, resp., (R = Me, CH2SiMe3, Ph), highly volatile organo-metallic compounds, which were isolated as analytically and spectroscopically pure oils by vacuum destillation. On the other hand, the protolysis reaction of 1a and 1b with excess of HCl gas affords monoimido complexes CpMo(NtBu)Cl3 (5a) and CpW(NtBu)Cl3 (5b), respectively.
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 0009-2940
    Keywords: Oxo complexes, organometallic ; Borato, hydrotris(3,5-dimethyl-1-pyrazolyl)1-, complexes ; Molybdenum complexes ; Tungsten complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Organometallic Oxo Complexes  -  Highervalent Derivatives of the d-Metal Acids, 6.  -  Hydrotris(3,5-dimethyl-1-pyrazolyl)borato-Substituted Alkyl(dioxo)1-, Methylenephosphoranyl(dioxo)1-, and s̰1-Allyl(dioxo) Complexes of Molybdenum and TungstenTp*MoO2Cl (1) and Tp*WO2Cl (2) [Tp* = κ31-HB(3,5-Me2pz)3] react with trimethyl aluminium to form the corresponding dioxo(methyl) complexes Tp*MO2(CH3), M=Mo (3), W (4). An X-ray crystal structure analysis of 3 is performed. The less oxidizing tungsten complex 2 is alkylated by Grignard reagents to yield alkyl complexes of the type Tp*WO2R 5-7 [R=CH2SiMe3, CH2tBu and CH2C(Me)Ph2] and the s̰1-2-methallyl complex Tp*WO2(CH2CMe=CH2) 8. Reactions of 2 with methylenephorphoranes R3P=CH2 (R=iPr, Ph) give transylidation products Tp*WO2(CHPiPr3) (9) and Tp*WO2(CH-PPh3) (10). Hydrolysis of 10 leads to a trioxotungstate [Tp*WO3]- (11), stabilized by a hydroxyphosphonium cation.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 0009-2940
    Keywords: Thianthrene 5-oxide ; Peroxide, bis(trimethylsilyl) ; Hydroperoxide, tert-butyl ; Oxygen transfer ; Peroxo complexes ; Catalysis ; Vanadium ; Molybdenum ; Tungsten ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Bis(trimethylsilyl) peroxide (BTSP) and tert-butyl hydroperoxide (tBuOOH) were activated by various oxo and peroxo complexes of molybdenum, tungsten, and vanadium as catalysts for the sulfoxidation of thianthrene 5-oxide (SSO). A screening of a number of phosphane oxide and amine oxide ligands revealed that BTSP was most efficiently activated by the [MoO5(OPtBu3)] complex. The best results for tBuOOH as oxygen source were achieved with the vanadates [VO(OR)3] (R = tBu, iPr). Comparative selectivity and rate data for the stoichiometric and catalytic sulfoxidations of SSO mediated by the MoO5L complex (L = OPtBu3, OPnOct3, ONnBu3, ONnOct3) suggest that the bisperoxo metal complex is the active oxygen transfer species.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
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