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Abstract The reactivity of phosphaalkynes, the isolobal and isoelectronic congeners to alkynes, with metal alkylidyne complexes is explored in this work. Treating the tungsten alkylidyne [tBuOCO]W≡CtBu(THF)2(1) with phosphaalkyne (10) results in the formation of [O2C(tBuC=)W{η2‐(P,C)−P≡C−Ad}(THF)] (13‐tBuTHF) and [O2C(AdC=)W{η2‐(P,C)−P≡C−tBu}(THF)] (13‐AdTHF); derived from the formal reductive migratory insertion of the alkylidyne moiety into a W−Carenebond. Analogous to alkyne metathesis, a stable phosphametallacyclobutadiene complex [tBuOCO]W[κ2‐C(tBu)PC(Ad)] (14) forms upon loss of THF from the coordination sphere of either13‐tBuTHFor13‐AdTHF. Remarkably, the C−C bonds reversibly form/cleave with the addition or removal of THF from the coordination sphere of the formal tungsten(VI) metal center, permitting unprecedented control over the transformation of a tetraanionic pincer to a trianionic pincer and back. Computational analysis offers thermodynamic and electronic reasoning for the reversible equilibrium between13‐tBu/AdTHFand14.
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This content will become publicly available on June 10, 2026
Synthesis, characterization, and thermal properties of volatile 1,4-dialkyl-5-silatetrazolines: nitrogen-rich silicon heterocycles as possible CVD precursors for silicon nitride
The synthesis and properties of three 1,4-dialkyl-5-silatetrazoline compounds (tBuNCHCHNtBu)Si(N4R2) are described, where R = Et,iPr, ortBu. These compounds may be useful as low temperature CVD precursors for silicon nitride thin films.
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- Award ID(s):
- 2400099
- PAR ID:
- 10656983
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Dalton Transactions
- Volume:
- 54
- Issue:
- 23
- ISSN:
- 1477-9226
- Page Range / eLocation ID:
- 9399 to 9404
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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