11B NMR of Two-Coordinate Boron
The preparation and investigation of boron compounds containing two-coordinate boron is still a great challenge for boron chemists. Until now this problem has been studied with limited success and only a few examples are known. The possibility of preparing cationic species of the type [R2N—B—NR2]+ by the reaction of (R2N)2BX with A1C13 or SbCl5 has been mentioned [68/57], but no report has appeared yet. The transition metal complexes [R2NBFe(CO)4] n or [BrBFe(CO)4] n may contain two-coordinate boron [70/15], but no structural data are available.