Synthesis and Investigation of [B₂₀H₁₇O(CH₂)₅]^3–, a Novel Solvent Complex of the [B₂₀H₁₈]^4–Ion

Abstract

Reaction of the [trans-B(20)H(18)](2-) ion with the n-butoxide ion, formed in situ from reaction of n-butanol and NaH, in tetrahydropyran (THP) produces in good yield an unexpected and isolable solvent-coordinated polyhedral borane anion, [ae-B(20)H(17)O(CH(2))(5)](3-). The anticipated product of nucleophilic attack, [ae-B(20)H(17)On-Bu](4-), is not observed under the reaction conditions. The solvent-coordinated product is also formed in the presence of either ethoxide or carbamate ion but is not observed if the ethoxide or carbamate ion is not present in stoichiometric amounts. In the presence of the n-butanethiol anion, the coordinated THP ring undergoes a ring-opening reaction, yielding the [ae-B(20)H(17)O(CH(2))(5)Sn-Bu](4-) anion. Ring opening is also observed in the presence of the ethoxide ion in refluxing THP. Isolation of the previously proposed analogous solvent-coordinated tetrahydrofuran (THF) product, [ae-B(20)H(17)O(CH(2))(4)](3-), was unsuccessful; however, the product resulting from ring opening of THF by the n-butanethiol anion is reported.

Reactivity of [WCl6] with Ethers: A Joint Computational, Spectroscopic and Crystallographic Study

“…Tetrahydropyran is a relatively stable cyclic ether, the opening of which has rarely been reported in the literature . In fact, thp ring‐opening by single C–O activation may be viable under forcing conditions,[23d], but the transformation of thp into 1,5‐dichloropentane (double C–O activation) is even more rare and was previously achieved as a non‐selective reaction by using TiCl 4 …”

Boron, aluminium, gallium, indium and thallium

“…60 The reaction of [trans-B 20 H 18 ] 2À towards sterically demanding nucleophiles in tetrahydropyran (THP) led to a solvent complex of the [B 20 H 18 ] 4À ion. 61 This journal is © The Royal Society of Chemistry 2013…”