Organometallics 

Abstract: This contribution describes a general method for the purification of solvents for use with air and moisture sensitive reactions. This procedure provides a nonhazardous alternative to distillations and vacuum transfers and does not require undue supervision or cooling, yet allows for the rapid collection of large quantities of extremely pure solvents on demand. Solvents are rigorously degassed in 18 L reservoirs and passed through two sequential purification columns. Protic contaminants are removed with activated alumina, while a supported copper catalyst is used to remove trace oxygen from hydrocarbons. The purification system is interfaced with either a glove box or Schlenk manifold for the anhydrous/anaerobic collection of solvents. Solvents purified by this method and tested with stock solutions of sodium benzophenone ketyl or titanocene dichloride/zinc dust are free of oxygen at least to the ppm level. Furthermore, this system may be used for the in-line purification of gases and is easily scaled down...

Abstract: Tables of 1H and 13C NMR chemical shifts have been compiled for common organic compounds often used as reagents or found as products or contaminants in deuterated organic solvents. Building upon the work of Gottlieb, Kotlyar, and Nudelman in the Journal of Organic Chemistry, signals for common impurities are now reported in additional NMR solvents (tetrahydrofuran-d8, toluene-d8, dichloromethane-d2, chlorobenzene-d5, and 2,2,2-trifluoroethanol-d3) which are frequently used in organometallic laboratories. Chemical shifts for other organics which are often used as reagents or internal standards or are found as products in organometallic chemistry are also reported for all the listed solvents.

Abstract: [Ag(Et2-Bimy)2][AgBr2] (1; Et2-Bimy = diethylbenzimidazol-2-ylidene) was obtained readily from the reaction of [Et2-BimyH]Br with Ag2O. Compound 2, [Ag(Et2-Bimy)2]PF6, was prepared by the reaction of [Et2-Bimy]PF6 with Ag2O under basic phase transfer catalysis conditions. Both compounds 1 and 2 are good carbene transfer agents. Thus, Pd(Et2-Bimy)2Cl2, Au(Et2-Bimy)Br, and [Au(Et2-Bimy)2]PF6 were obtained in high yields using 1 and 2 as carbene sources. The byproduct AgBr or AgCl can be reused to generate 1 under basic phase transfer catalysis conditions. The crystal structure of compound 1 revealed that linear [Ag(Et2-Bimy)2]+ and [AgBr2]- groups were associated through a short AgI−AgI contact (2.956 A). FAB/mass spectrometry and molar conductivity measurements indicate the existence of ligand-unsupported AgI−AgI interactions in the gas phase and acetonitrile solution. 13C NMR studies suggest that the two Bimy ligands in 1 are fluxional in solution.