Reaction of a stable digermyne with ethylene afforded the corresponding 1,2-digermacyclobutene. Depending on the reaction conditions applied, further reaction of this 1,2-digermacyclobutene with ethylene furnished two different reaction products: a 1,4-digerma-bicyclo[2.2.0]hexane or a bis(germiranyl)ethane.

We expected that the chemical trapping products of low‐coordinated tellurenyl cation species can also be kinetically stabilized by the Tbt or Bbt group. Recently, we have reported the halogenation reactions of Bbt‐substituted ditelluride, BbtTeTeBbt, leading to the formation of the TeII–TeIV mixed‐valent tellurenyl fluoride, BbtTeTe(F)2Bbt, and tellurenyl halides, BbtTeX (X = Cl, Br, I). During the dehalogenation reactions of these tellurium halides, it is rational to postulate the formation of a tellurenyl cation species as an intermediate. In this paper, we report the successful trapping of tellurenyl cation species with butadienes or triphenylphosphane, and the regeneration of the tellurenyl cation species by thermal retro [1+4] cycloaddition of the diene adducts.

Halogenation reactions of BbtTeTeBbt (Bbt;2,

Bis(methylene)-λ -sulfane 1, a >C=S=C< heterocumulene, was obtained as a red crystalline solid from the reaction between elemental sulfur and a carbenoid that contains sterically demanding silylalkyl groups. Under atmospheric conditions, and even at elevated temperatures, 1 exhibits extraordinary stability. The molecular structure and electron-density distribution of 1 were analyzed by single-crystal X-ray diffraction analysis, which revealed a bent C=S=C geometry with C=S=C π-bonds. These results, combined with those of variable-temperature NMR measurements and theoretical calculations suggest a slow rotation of the S=C moieties in 1, the stability and structure of which were further examined by theoretical calculations.