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Equilibrium Formation of Stable All-Silicon Versions of 1,3-Cyclobutanediyl.

ABSTRACT: Main group analogues of cyclobutane-1,3-diyls are fascinating due to their unique reactivity and electronic properties. So far only heteronuclear examples have been isolated. Here we report the isolation and characterization of all-silicon 1,3-cyclobutanediyls as stable closed-shell singlet species from the reversible reactions of cyclotrisilene c-Si3 Tip4 (Tip=2,4,6-triisopropylphenyl) with the N-heterocyclic silylenes c-[(CR2 CH2 )(NtBu)2 ]Si: (R=H or methyl) with saturated backbones. At elevated temperatures, tetrasilacyclobutenes are obtained from these equilibrium mixtures. The corresponding reaction with the unsaturated N-heterocyclic silylene c-(CH)2 (NtBu)2 Si: proceeds directly to the corresponding tetrasilacyclobutene without detection of the assumed 1,3-cyclobutanediyl intermediate.

SUBMITTER: Yildiz CB

PROVIDER: S-EPMC7496386 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Equilibrium Formation of Stable All-Silicon Versions of 1,3-Cyclobutanediyl.

Yildiz Cem B CB Leszczyńska Kinga I KI González-Gallardo Sandra S Zimmer Michael M Azizoglu Akin A Biskup Till T Kay Christopher W M CWM Huch Volker V Rzepa Henry S HS Scheschkewitz David D

Angewandte Chemie (International ed. in English) 20200615 35

Main group analogues of cyclobutane-1,3-diyls are fascinating due to their unique reactivity and electronic properties. So far only heteronuclear examples have been isolated. Here we report the isolation and characterization of all-silicon 1,3-cyclobutanediyls as stable closed-shell singlet species from the reversible reactions of cyclotrisilene c-Si3 Tip4 (Tip=2,4,6-triisopropylphenyl) with the N-heterocyclic silylenes c-[(CR2 CH2 )(NtBu)2 ...[more]

PMID: 32407571

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