Terminal tungsten pnictide complex formation through pnictaethynolate decarbonylation

Abstract

Treatment of a four-coordinate tungsten(iv) complex with pnictaethynolate ions installs terminal tungsten–nitrogen, –phosphorus, and –arsenic triple bondsviadecarbonylation.

The Chemistry of the 2‐Phosphaethynolate Anion

“…[55] Indeed, simply mixing [W(ODipp) 4 ]w ith Na(OCX) yields under decarbonylation the desired salts [Na(L) x ] + [WX-(ODipp) 4 ] À in excellent to moderate yields,w hereby the rate of conversion increases in the order N < P < As.A ll species are diamagnetic with slightly distorted square-pyramidal structures.Notably,the scalar 1 J W-X coupling constants indicate that the s-orbital contribution in the W Xb ond decreases from Nt oPtoAs. Confirmation for the viability of path (a) comes from as tudy where the d 2 valence-configured tungsten(IV) alkoxide complex [W-(ODipp) 4 ]w as reacted with Na(OCX) (X = N, P, As) in DME or in the presence of 12-crown-4 (12c4) (Scheme 13).…”

Limitations of Steric Bulk: Towards Phospha‐germynes and Phospha‐stannynes

“…All of the aforementioned species were generated by photolysis of phosphaketenes, which lose carbon monoxide acting as a source of a monoanionic phosphide (P − ). This strategy has recently been shown to be a general route to terminal nitrides, phosphides and arsenides by Cummins and co‐workers who were able to isolate anionic tungsten complexes such as E …”

“…[30][31][32] All of the aforementioned speciesw ere generated by photolysis of phosphaketenes, whichl ose carbon monoxidea cting as as ource of am onoanionic phosphide (P À ). This strategyh as recently been shown to be ag eneralr oute to terminal nitrides, phosphides and arsenides by Cummins and co-workers who were able to isolate anionic tungsten complexes such as E. [33] In ordert og enerate stable neutral terminal phosphides of the main group elements (nitrile analogues), the particular challengei sto develop am onodentates ubstituent sufficiently bulky to preventt he oligomerisationo rd imerisationo fR EP (E = Ge, Sn) fragments. With this in mind, we decided to further develop the class of aryl(silyl)amides to obtain monomeric phospha-germynesa nd phospha-stannynes,a st his class of substituents has been successfully employed by the Jones groupf or the isolation of lowc oordinate compounds.…”

Trapping of a Highly Bent and Reduced Form of 2‐Phosphaethynolate in a Mixed‐Valence Diuranium–Triamidoamine Complex

“…[4] Consequently,d espite the increasingly burgeoning nature of the area there are still many unanswered questions about the intrinsic properties and coordination chemistry of the OCP À anion. [1,5] This is perhaps unsurprising since as aclosed-shell anion OCP À would be expected to inherently resist reduction as this would populate antibonding orbitals,a nd indeed where examples of reduction have been reported fragmentation of the OCP À unit is usually the decisive,inevitable result. [1,5] This is perhaps unsurprising since as aclosed-shell anion OCP À would be expected to inherently resist reduction as this would populate antibonding orbitals,a nd indeed where examples of reduction have been reported fragmentation of the OCP À unit is usually the decisive,inevitable result.…”

“…[1] Although the oxidation chemistry of the OCP À anion is now quite established, [1] reports of its formal reduction chemistry are exceedingly scarce. [1,5] This is perhaps unsurprising since as aclosed-shell anion OCP À would be expected to inherently resist reduction as this would populate antibonding orbitals,a nd indeed where examples of reduction have been reported fragmentation of the OCP À unit is usually the decisive,inevitable result. Forexample,strongly reducing [U{N(OAr Ad,Me ) 3 }(DME)] [N(OAr Ad,Me ) 3 = trianion of tris(2hydroxy-3-(1-adamantyl)-5-methylbenzyl)amine] cleaves the CÀObond of OCP À to give an oxo-bridged dinuclear product containing cyaphide,CP À , [6] whereas the more weakly reducing [Ti(OCP){HC(CMeNAr) 2 }(OAr)] (Ar = 2,6-diisopropylphenyl) cleaves the C À Pb ond to release CO and give aP 2 derivative.…”