RESUMEN
The title compound, poly[µ-aqua-aqua-µ(6)-(1,1-dioxo-1λ(6),2,5-thia-diazo-lidine-3,4-diolato)-dilithium], [Li(2)(C(2)N(2)O(4)S)(H(2)O)(2)](n) or (H(2)O)(2):Li(2)TDD, forms an infinite three-dimensional structure containing five-coordinate (Li/5) and six-coordinate (Li/6) Li(+) cations. Li/5 is coordinated by three water mol-ecules, one carbonyl O atom and one sulfuryl O atom while Li/6 is coordinated by one water mol-ecule, three carbonyl O atoms, and two sulfuryl O atoms. Each water mol-ecule bridges two Li(+) cations, while also hydrogen bonding to either one endocyclic N atom and one sulfuryl O atom or two endocyclic N atoms. While the endocyclic N atoms in the anion do not coordinate the Li(+) cations, the carbonyl and sulfuryl groups each coordinate three Li(+) cations, which gives rise to the infinite three-dimensional structure.
RESUMEN
Monomeric Cu(I) amido and thiolate complexes that are supported by the N-heterocyclic carbene ligand 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (IPr) catalyze the hydroamination and hydrothiolation of electron-deficient vinylarenes with reactivity patterns that are consistent with an intermolecular nucleophilic addition of the amido/thiolate ligand of (IPr)Cu(XR) (X = NH or S; R = Ph, CH2Ph) to free vinylarene.
RESUMEN
A series of monomeric (NHC)Cu(SR) (R = Ph or CH2Ph; NHC = N-heterocyclic carbene) complexes have been synthesized and fully characterized including single-crystal X-ray diffraction studies. These complexes catalyze the addition of S-H bonds across electron-deficient olefins to regioselectively produce "anti-Markovnikov" products.
Asunto(s)
Alquenos/química , Cobre/química , Electrones , Hidrógeno/química , Compuestos de Sulfhidrilo/química , Azufre/química , Catálisis , Ligandos , Modelos Moleculares , Conformación MolecularRESUMEN
Monomeric copper(I) alkyl complexes that possess the N-heterocyclic carbene (NHC) ligands IPr, SIPr, and IMes [IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene, SIPr = 1,3-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene, IMes = 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene] react with amines or alcohols to release alkane and form the corresponding monomeric copper(I) amido, alkoxide, or aryloxide complexes. Thermal decomposition reactions of (NHC)Cu(I) methyl complexes at temperatures between 100 and 130 degrees C produce methane, ethane, and ethylene. The reactions of (NHC)Cu(NHPh) complexes with bromoethane reveal increasing nucleophilic reactivity at the anilido ligand in the order (SIPr)Cu(NHPh) < (IPr)Cu(NHPh) < (IMes)Cu(NHPh) < (dtbpe)Cu(NHPh) [dtbpe = 1,2-bis(di-tert-butylphosphino)ethane]. DFT calculations suggest that the HOMO for the series of Cu anilido complexes is localized primarily on the amido nitrogen with some ppi(anilido)-dpi(Cu) pi-character. [(IPr)Cu(mu-H)]2 and (IPr)Cu(Ph) react with aniline to quantitatively produce (IPr)Cu(NHPh)/dihydrogen and (IPr)Cu(NHPh)/benzene, respectively. Analysis of the DFT calculations reveals that the conversion of [(IPr)Cu(mu-H)]2 and aniline to (IPr)Cu(NHPh) and dihydrogen is favorable with DeltaH approximately -7 kcal/mol and DeltaG approximately -9 kcal/mol.