Diborheterocyclen: Oxadiborolan – Oxadiborinan – Diazadiborinan

Diboron Heterocyclic Compounds: Oxadiborolane – Oxadiborinane – Diazadiborinane The diboryl compounds R(Cl)B(CH₂)_nB(Cl)R (R ? Cl or CH₃; n = 2, 3) and the silylated or stannylated starting materials [(CH₃)₃Y]₂X (Y ? Si or Sn; X ? S, NCH₃, O, NCH₃? NCH₃) were used for (5+1)- and (4+2)-cyclocondensation reactions. Dimethylether was an additional starting molecule. While no thiadiborinanes could be isolated, the nitrogen or oxygen containing heterocycles were formed in varying yields. Synthesis and properties of these compounds are described.