11B NMR Study of CeB2C2

1H and 11B NMR study of p-toluene boronic acid and anhydride.

11B NMR study of p-carboxybenzeneboronic acid ions for complex formation with some monosaccharides.

The 11B NMR spectra of p-carboxybenzeneboronic acid (PCBA) ions demonstrated that their chemical shifts depend on the pH. At a lower pH, PCBA exists as a mixture of neutral PCBA and the monoanion with a trigonal structure, and at higher pH as the dianion with a tetrahedral structure. In the intermediate pH region, both the mono- and dianion coexist. The pKa of the monoanion of PCBA has been est...

Structural Study of xNa2S + (1 − x)B2S3 Glasses and Polycrystals by Multiple-Quantum MAS NMR of 11B and 23Na

Glasses and polycrystals in the series xNa2S + (1 − x)B2S3 have been prepared and studied by magic angle spinning (MAS) NMR and by two-dimensional multiple-quantum (MQ) MAS NMR of11B and 23Na. These techniques, when applied at various magnetic fields and combined with computer simulations of the spectra, provide new insights into the structure of the polycrystalline samples. Isotropic chemical ...

11B NMR Investigations of Borate Esters in Aqueous Solutions and Wine

The element boron plays a role in medical and biological fluids [1] which is not yet well investigat­ ed. Further it is questionable if boron is needed as a trace element in the hum an food. But due to its toxicity, boron containing drugs are largely for­ bidden in this country [2], With the daily food, boron is incorporated in amounts which are esti­ mated to 1 through 40 mg per day [3], where...

Assignment of the 11b Nmr Spectrum of the Tridecahydro Decaborate(1-) Ion

IN A VARIETY of donor solvents, decaborane behaves as a monoprotic acid and, upon treatment with suitable bases such as amines or ylides, affords the tridecahydrodecaborate(1-) ion, B10H13-[1]. Previous HB NMR studies[2], done at lower field strengths, did not allow an interpretation of these spectra. In this communication, spectra of B~0HI~and some of its derivatives, recorded at 70.6 MHz, are...