Staudinger Reactivity and Click Chemistry of Anthracene (A)-Based Azidophosphine N₃PA

Abstract

11-Azido-9,10-dihydro-9,10-phosphanoanthracene (N 3 PA) has been demonstrated recently as a transfer reagent for molecular phosphorus mononitride (PN) because it easily dissociates at room temperature into dinitrogen (N 2 ), PN, and anthracene (A). Here we report further reactivity studies of the N 3 PA molecule including strain-promoted 1,3-dipolar cycloaddition with cyclooctyne and Staudinger-type reactivity. Calculations at the DLPNO-CCSD(T)/cc-pVTZ//PBE0-D3(BJ)/cc-pVTZ level of theory indicate that the click reaction is faster than the dissociation of N 3 PA. The Staudinger-type reactivity enabled transfer of the NPA fragment to a base-stabilized silylene. The previously reported intermediate of vanadium trisanilide with an NPA ligand could be isolated in 61% yield and structurally characterized in a single-crystal X-ray diffraction experiment. In line with the previously reported phosphinidene reactivity of the transient vanadium phosphorus mononitride complex, thermolysis or irradiation of the complex leads to A elimination and formation of the corresponding vanadium PN dimer or trimer, respectively.

Reactions of main group compounds with azides forming organic nitrogen-containing species

“…In 2022, Cummins et al investigated the Staudinger reactivity and click chemistry of azidophosphine P3 (Scheme 117). 187 Treatment of P3 with excess cyclooctyne resulted in the formation of triazole P3-P6 in 60% yield through the 1,3-dipolar cycloaddition. Compound P3-P6 is unstable and upon heating at 80 °C, P3-P7 is formed via the [1,2] shift of the P-anthracene unit from the side N atom to the central N atom in the triazole ring.…”

Synthesis of Carbene-Stabilized PNPN Fragments and Their Carbene-Dependent Redox Properties

“…Phosphorus mononitride (PN) is a molecule of long-standing fundamental intrigue, − owing both to it being the first phosphorus compound detected in interstellar media , and its isoelectronic relationship with small molecules of critical importance, such as N 2 , CO, and HCCH. In spite of this, the synthesis of PN-containing compounds is limited (Chart ), − due to its proclivity to undergo uncontrolled oligomerization to insoluble, ill-defined, material. , As linear and cyclic oligomers of PN should be isoelectronic with polyenes and polyaromatic hydrocarbons, respectively, and accordingly may exhibit interesting electronic properties, they are attractive synthetic targets of both fundamental and applied interest. ,,, While numerous compounds consisting of catenated, low-valent, heavy pnictogens such as phosphorus and arsenic are known, ,− their synthesis is often dependent on the direct functionalization of elemental P 4 or As 4 , preventing the direct transposition of these strategies to PN. Further, compounds containing linear chains of more than three nitrogen atoms are far rarer, , owing to their thermodynamic and kinetic instabilities toward dinitrogen extrusion, and, to our knowledge, no general strategies for the controlled synthesis for low-valent heteropnictogen chains are known.…”

Chemoselective Staudinger Reactivity of Bis(azido)phosphines Supported with a π-Donating Imidazolin-2-iminato Ligand

“…Azidophosphines have functioned as precursors to interesting phosphorus species (Scheme 3), including an NHIsupported phosphine, 22 a bis(NHI)-supported phosphinonitrene (R 2 P�N), 23−25 phosphinidene (R−P), 26 phosphinidene chalcogenide (RP�Ch), 27 phosphorus mononitride (P� N), 28−30 and a phosphorus-substituted triazole via a click reaction. 29 We sought to explore the synthesis of phosphorus species containing both a π-donating phosphinimine ligand and a bulky, π-donating NHI ligand to prepare electron-rich phosphines. Electron-rich phosphine ligands have already demonstrated their application as ligands in catalytic transformations, 31,32 and P-stereogenic phosphines further hold promise as ligands in asymmetric catalysis.…”