The negative ions of triphenylene and coronene give striking spectral simplifications in the NM R spectra of polyglycoldimethylethers (glymes) by virtue of reversible complexation, leading to isotropic Fermi contact shifts. In this aspect they resemble the lanthanide shift reagents, such as tris(dipivaIomethanato)-europimn and -praseodymium. The NM R spectra of glymes complexed with both types of shift re agents have been measured. Similarities but also difFerences were found, as manifested by measuring partially deuterated glymes. Information is obtained on the structure of the complexes and on the mechanisms of spin transfer from the radical center to the glymes.

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In order to find characteristic differences between symmetrically and unsymmetrically bonded N,N‐dialkyldithiocarbamates, their IR and 1H NMR spectra have been examined. The IR data firmly underline a previously reported infrared criterion which makes it possible to distinguish the two types of bonding. In the spectra of the unsymmetrical N,N‐diethyldithiocarbamates a band at 1000 cm−1 is assigned to the CS stretching mode. Although the rotation around the S2C‐NR2, bond in several dithiocarbamato complexes will be strongly hindered at low temperatures, no splitting of the NMR signals of the N‐alkyl groups could be observed. This may be attributed to an extremely small difference in magnetic environment of the N‐alkyl moieties in the rotamers.

Publication costs assisted by the National Science Foundation and the Petroleum Research Fund Densities and viscosities of solutions of NaBPh4 in tetrahydrofuran and 2-methyltetrahydrofuran were measured as a function of salt concentration and temperature. The concentration dependence of the viscosity can best be described by the Vand equation for the viscosity of concentrated dispersions, the moving entity being a solvent-separated ion pair the shape of which can be approximated by a prolate elipsoid of axial ratio 2. Between 0.05 and 0.5 m NaBPh4 in THF at 20°the ratio cm/log pr is nearly constant. The effective volume Ve°o f the flowing unit was found to be 0.72 M-1 at 20°, and increases at lower temperature according to the relationship log Ve°= -0.613 + 138/T. A Ve°v alue of 0.72 M-1 is consistent with conductance data on NaBPh4 solutions which show that NaBPh4 is a solvent-separated ion pair in THF. Approximately six THF molecules may be bound to the Na+ ion. On addition of glymes {e.g., hexaethylene glycol dimethyl ether or glyme 7) the THF solvation shell is replaced by the glyme, and a plot of vs. the glyme to salt ratio shows a distinct break at a ratio of unity. Crystalline 1:1 complexes of NaBPh4 with glyme 5, glyme 6, and glyme 7 were obtained, as well as a 2:1 complex with glyme 4.

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