1,2-BIS(DIISOPROPYLAMINO)-1,2-DIHYDRO-1,2-BENZODIBORETE - A 1ST THERMALLY STABLE 1,2-DIHYDRO-1,2-DIBORETE

The synthesis of 1,2-bis(diisopropylamino)-1,2-dihydro-1,2-benzodiborete (7) succeeds in good yield by a twofold ipsoborylation of 1,2-bis(trimethylsilyl)benzene to give 3, double amination to afford 4 and subsequent coupling with sodium/potassium alloy. Crystalline 7 is thermally stable; an X-ray crystallographic structure determination has been carried out. In concentrated solution reaction of 4 with sodium/potassium alloy predominantly leads to the formation of the tetraborocine 6 by dimerization. In the presence of (phthalocyaninato)palladium as catalyst 7 reacts with 2 equivalents of dimethylacetylenedicarboxylate to give the benzo-annulated diborocine 12.