Silylenecyclotetrasilane 4 synthesized as marginally stable orange crystals undergoes ring expansion to give cyclopentasilene 5 quantitatively with the activation parameters of δH ‡ = 24.8 ± 1.0 kcal mol-1 and δS ‡ = +6.5 ± 3.2 cal mol-1 K-1. The activation parameters and DFT calculations support that the isomerization of 4 to 5 proceeds through stepwise double 1,2-silyl migrations.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry