Hydrogen- and Fluorine-Bridged Disilyl Cations and Their Use in Catalytic C−F Activation

The hydrogen-bridged disilyl cation 6 with an 1,8-naphthalenediyl backbone was synthesized and was characterized by NMR spectroscopy and X-ray crystallography, supported by quantum mechanical computations. The SiHSi linkage is symmetrical, corresponding to a single minimum potential, and the structural parameters are in agreement with the presence of a two electron−three center bond in 6. Treatment of disilyl cation 6 with alkyl fluorides yields the disilylfluoronium ion 10. The SiFSi group in the disilyl fluoronium ion 10 is symmetrical with an average SiF bond length of 175.9(8) and a bent angle β = 130°. Both cations catalyze the hydrodefluorination reaction of alkyl and benzyl fluorides to give alkanes

Hydrogen- and Fluorine-Bridged Disilyl Cations and Their Use in Catalytic C−F Activation

The hydrogen-bridged disilyl cation 6 with an 1,8-naphthalenediyl backbone was synthesized and was characterized by NMR spectroscopy and X-ray crystallography, supported by quantum mechanical computations. The SiHSi linkage is symmetrical, corresponding to a single minimum potential, and the structural parameters are in agreement with the presence of a two electron−three center bond in 6. Treatment of disilyl cation 6 with alkyl fluorides yields the disilylfluoronium ion 10. The SiFSi group in the disilyl fluoronium ion 10 is symmetrical with an average SiF bond length of 175.9(8) and a bent angle β = 130°. Both cations catalyze the hydrodefluorination reaction of alkyl and benzyl fluorides to give alkanes

Hydrogen- and Fluorine-Bridged Disilyl Cations and Their Use in Catalytic C−F Activation

The hydrogen-bridged disilyl cation 6 with an 1,8-naphthalenediyl backbone was synthesized and was characterized by NMR spectroscopy and X-ray crystallography, supported by quantum mechanical computations. The SiHSi linkage is symmetrical, corresponding to a single minimum potential, and the structural parameters are in agreement with the presence of a two electron−three center bond in 6. Treatment of disilyl cation 6 with alkyl fluorides yields the disilylfluoronium ion 10. The SiFSi group in the disilyl fluoronium ion 10 is symmetrical with an average SiF bond length of 175.9(8) and a bent angle β = 130°. Both cations catalyze the hydrodefluorination reaction of alkyl and benzyl fluorides to give alkanes

The Sodium Siloxides (<i>t</i>Bu₃SiONa)₄ and (<i>t</i>Bu₂PhSiONa)₄: Synthesis and X-ray Crystal Structure Analysis

The sodium siloxides (tBu3SiONa)4 and (tBu2PhSiONa)4 can be synthesized almost quantitatively from the reaction of the sodium silanides tBu3SiNa and tBu2PhSiNa with N2O in tetrahydrofuran at −78 °C. (tBu3SiONa)4 and (tBu2PhSiONa)4 are the first structurally characterized sodium siloxides featuring a heterocubane framework in the solid state. X-ray quality crystals of the supersilanol, tBu3SiOH (monoclinic, C2/c), were obtained from the thermolysis of tBu3SiNaN−NNSitBu3 in the presence of water

The Sodium Siloxides (<i>t</i>Bu₃SiONa)₄ and (<i>t</i>Bu₂PhSiONa)₄: Synthesis and X-ray Crystal Structure Analysis

The sodium siloxides (tBu3SiONa)4 and (tBu2PhSiONa)4 can be synthesized almost quantitatively from the reaction of the sodium silanides tBu3SiNa and tBu2PhSiNa with N2O in tetrahydrofuran at −78 °C. (tBu3SiONa)4 and (tBu2PhSiONa)4 are the first structurally characterized sodium siloxides featuring a heterocubane framework in the solid state. X-ray quality crystals of the supersilanol, tBu3SiOH (monoclinic, C2/c), were obtained from the thermolysis of tBu3SiNaN−NNSitBu3 in the presence of water

The Sodium Cuprate (<i>t</i>Bu₃Si)₂CuNa: Formation and X-ray Crystal Structure Analysis

(tBu3Si)2CuNa(THF)n (1; n = 2, 4) is the first structurally characterized sodium cuprate and represents a heavier homologue of the well-known lithium cuprates. Yellow crystals of (tBu3Si)2CuNa(THF)2 (1a) were obtained from heptane (space group P21/n); the ion-separated form (tBu3Si)2CuNa(THF)4 (1b) crystallized from toluene (space group R3̄)

The Sodium Siloxides (<i>t</i>Bu₃SiONa)₄ and (<i>t</i>Bu₂PhSiONa)₄: Synthesis and X-ray Crystal Structure Analysis

The sodium siloxides (tBu3SiONa)4 and (tBu2PhSiONa)4 can be synthesized almost quantitatively from the reaction of the sodium silanides tBu3SiNa and tBu2PhSiNa with N2O in tetrahydrofuran at −78 °C. (tBu3SiONa)4 and (tBu2PhSiONa)4 are the first structurally characterized sodium siloxides featuring a heterocubane framework in the solid state. X-ray quality crystals of the supersilanol, tBu3SiOH (monoclinic, C2/c), were obtained from the thermolysis of tBu3SiNaN−NNSitBu3 in the presence of water

The Sodium Siloxides (<i>t</i>Bu₃SiONa)₄ and (<i>t</i>Bu₂PhSiONa)₄: Synthesis and X-ray Crystal Structure Analysis

The sodium siloxides (tBu3SiONa)4 and (tBu2PhSiONa)4 can be synthesized almost quantitatively from the reaction of the sodium silanides tBu3SiNa and tBu2PhSiNa with N2O in tetrahydrofuran at −78 °C. (tBu3SiONa)4 and (tBu2PhSiONa)4 are the first structurally characterized sodium siloxides featuring a heterocubane framework in the solid state. X-ray quality crystals of the supersilanol, tBu3SiOH (monoclinic, C2/c), were obtained from the thermolysis of tBu3SiNaN−NNSitBu3 in the presence of water

Asymmetric Synthesis of Palladacycles by Regioselective Oxidative Cyclization of <i>C</i>₂-Symmetrical, Chiral Alkenes and Determination of the Configuration of All Stereocenters

The reaction of Pd2(dba)3·CHCl3 with 2 equiv of chiral, C2-symmetrical cyclopropenes bearing lactate esters at the 1- and 2-positions provided trans-5-palladatricyclo[4.1.0.02,4]heptanes (PTHs) in high diastereomeric excess. The configuration of all stereocenters in the major diastereomer was determined by X-ray structure analyses of the complexes of the PTH with norbornadiene; the C2 symmetry of the (+)-DIOP complex of the minor diastereomer proves that this was also a trans isomer

Twisted Imide Bond in Noncyclic Imides. Synthesis and Structural and Vibrational Properties of <i>N</i>,<i>N</i>-Bis(furan-2-carbonyl)-4-chloroaniline

A novel imide compound (C₁₆H₁₀ClNO₄) was synthesized in a single step by the reaction of 2-furoic acid with 4-chloroaniline in a 2:1 molar ratio using carbonyldiimidazole (CDI) in dry THF. The structure was supported by spectroscopic and elemental analyses and the single-crystal X-ray diffraction data. Crystallographic studies revealed that the compound crystallized in a monoclinic system with space group <i>P</i>2₁/<i>c</i> and unit cell dimensions <i>a</i> = 12.2575(5) Å, <i>b</i> = 7.7596(2) Å, <i>c</i> = 15.0234(7) Å, α = γ = 90°, β = 92.771(4)°, <i>V</i> = 1427.25(10) ų, <i>Z</i> = 4. The imide bond is twisted, and the OC–N–C­(O) units deviate significantly from planarity with dihedral angles around the imide group reaching ca. −150.3° (C1–N1–C2–O21 = −148.8° and C2–N1–C1–O11 = −151.9°). The nonplanarity of the imide moiety and the related conformational properties are discussed in a combined approach that includes the analysis of the vibrational spectra together with theoretical calculation methods, especially in terms of natural bond orbital (NBO) calculations