A homoleptic cyanoborate with nucleophilic boron atom: An unprecedented dianion in the salts M2[B(CN)3] (M=Li, Na, K) with nucleophilic boron in the formal oxidation state +1 was obtained by reductive BC bond cleavage in the [B(CN)4]− anion and characterized by NMR (11B, 13C), vibrational spectroscopy and single crystal X‐ray diffraction.
Ionic liquids (ILs) are novel and chemically inert solvents for a wide range of reactions in organic synthesis and biocatalysis, and at least one of them is known to dissolve cellulose. ILs would provide novel options for cellulose degradation in homogenous catalysis if cellulases were sufficiently stable and active. By screening metagenomic libraries 24 novel cellulase clones were identified and tested for their performance in the presence of ILs. Most enzyme clones showed only very poor or no activities. Three enzyme clones (i.e. pCosJP10, pCosJP20 and pCosJP24) were moderately active and stable in the presence of 1-butyl-1-methyl-pyrrolidinium trifluoromethanesulfonate. The corresponding genes of these environment-derived cosmids were similar to known cellulases from Cellvibrio japonicus and a salt-tolerant cellulase from an uncultured microorganism, S.
The industrial product (C(2)F(5))(3)PF(2) is transformed into the phosphinic acid chloride (C(2)F(5))(2)P(O)Cl, which reacts with an excess of Bu(3)SnH in a clean, multistep reaction to give the stannyl derivative (C(2)F(5))(2)POSnBu(3). Subsequent treatment with gaseous HBr leads to the formation of (C(2)F(5))(2)POH, which is isolated in 70 % yield. Besides (CF(3))(2)POH, bis(pentafluoroethyl)phosphinous acid, (C(2)F(5))(2)POH, represents the second known example of a phosphinous acid that is predicted by using density functional theory calculations at the B3PW91/6-311G(3d,p) level to be more stable than the phosphane oxide tautomer, the energy difference being 11.7 kJ mol(-1). Only the phosphinous acid isomer is detectable in the gas phase and in solution. However, investigations of the neat liquid reveal a temperature-dependent tautomeric equilibrium with the phosphane oxide isomer (C(2)F(5))(2)P(O)H, which is characterized by vibrational and multinuclear NMR spectroscopic methods in combination with quantum-chemical calculations.
Straightforward syntheses of selected nondeuterated, partially deuterated, and fully deuterated room temperature ionic liquids (ILs) with the anions tris(pentafluoroethyl)trifluorophosphate, tetracyanoborate, and methyl sulfate were developed. The viscosity and the density of these ionic liquids were measured at various temperatures. The dissociation rate of the ionic liquid, the sizes of the cation and the anion, and the nature of the inter-ionic interaction are not influenced by deuteration, but viscosity is. All deuterated ionic liquids possess a higher viscosity and density in comparison to non-deuterated ones. The explanation of this phenomenon is given and discussed based on the modified Stokes-Einstein equation with a parameter which reflects the mass of the diffused particles. This new knowledge supports the recent development of novel low viscous inert ionic liquids which are of particular interest for the application in energy conversion devices. Deuterated ionic liquids are valuable media for the investigation of chemical reactions, natural products, and bio-materials by means of the NMR spectroscopy.
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