Cobalt‐Mediated [3+1] Fragmentation of White Phosphorus: Access to Acylcyanophosphanides

Abstract

Despite the accessibility of numerous transition metal polyphosphido complexes through transition‐metal‐mediated activation of white phosphorus, the targeted functionalization of Pn ligands to obtain functional monophosphorus species remains challenging. In this study, we introduce a new [3+1] fragmentation procedure for cyclo‐P4 ligands, leading to the discovery of acylcyanophosphanides and ‐phosphanes. Treatment of the complex [K(18c‐6)][(Ar*BIAN)Co(η4‐P4)] ([K(18c‐6)]3, BIAN = 1,2‐bis(arylimino)acenaphthene diimine) with acyl chlorides results in the formation of acylated tetraphosphido complexes [(Ar*BIAN)Co(η4‐P4C(O)R)] (R = tBu, Cy, 1‐Ad, Ph; 4a‐d). Subsequent reaction of 4a‐d with cyanide salts yields acylated cyanophosphanides [RC(O)PCN]− (9a‐d−) and the cyclo‐P3 cobaltate anion [(Ar*BIAN)Co(η3‐P3)(CN)]− (8−). Further reactions of 4a‐d with trimethylsilyl cyanide (Me3SiCN) and isocyanides provide insight into a plausible mechanism of this [3+1] fragmentation reaction, as these reagents partially displace the P4C(O)R ligand from the cobalt center. Several potential intermediates of the [3+1] fragmentation were characterized. Additionally, the introduction of a second acyl substituent was achieved by treating [K(18c‐6)]9b with CyC(O)Cl, resulting in the first bis(acyl)monocyanophosphine (CyC(O))2PCN (10).

Nitrogen, Sulfur Co-doped Hollow Carbon-Encapsulated Cu/Co2P for Selective Oxidation Esterification of Furfurals

“…This difference may be attributed to the combination of cobalt atoms with the introduced phosphorus atoms, resulting in an increase in the Co–Co bond length . Typical length of Co–P single bonds in organometallic complexes falls within the range of 2.1–2.3 Å. , The Co–P bond lengths in Co 2 P@C-NS and Cu/Co 2 P@C-NS-36 nm are 2.19 and 2.23 Å (Table S4), respectively, falling within the range of a typical Co–P single bond in organometallic complexes. Notably, these lengths exceed those found in phosphorus complexes with planar geometry, which are approximately 2.05 Å .…”

Functionalization of Tetraphosphido Ligands by Heterocumulenes

“…In a recent study, we reported the anionic cyclo -P 4 complex [(Ar*BIAN)Co(η 4 -P 4 )] − ( 1 – , Figure b) and its reaction with acyl chlorides, yielding the functionalized cyclo -P 4 complex [(Ar*BIAN)Co(η 3 :η 1 -P 4 C(O) t Bu] ( 2 ) . When compound 2 was treated with nitriles or isocyanides, there was a partial displacement of the P 4 C(O)R ligand from the cobalt center.…”

Cobalt‐Mediated [3+1] Fragmentation of White Phosphorus: Access to Acylcyanophosphanides

“…Figure 3. a) Solid-state molecular structure of [(Ar*BIAN)Co-(Me 3 SiNC)(η 2 : η 1 -P 4 COtBu)] (5 a);[45] thermal ellipsoids are shown at the 50 % probability level; hydrogen atoms and disorder are omitted for clarity. Selected bond lengths [Å] and angles [°]: P1À P2 2.1961(1), P2À P3 2.207(1), P3À P4 2.1355(1), Co1À P1 2.2895(7), Co1À P3 2.3330(8), Co1À P4 2.2987(8), C4À O1 1.432(3), P4À O1 1.6722(2), Co1À C3 1.851(2), Co1À C3À N3 174.3(2), C3À N3À Si1 176.14(2); b) experimental (upward) and simulated (downward) 31 P{ 1 H} NMR spectra of 5 a with nuclei assigned to an AEMX spin system: δ(P A ) = 228.1 ppm, δ(P E ) = À 10.7 ppm, δ(P M ) = À 102.4 ppm, δ(P X ) -= À 245.1 ppm, 1 J AM = À 355 Hz, 1 J MX = À 267 Hz, 1 J EX = À 64 Hz, 2 J AX = 8 Hz, 2 J ME = 9 Hz, 3 J AE = À 11 Hz.…”

“…Figure 4. Solid-state molecular structures of a) endo-[(Ar*BIAN)Co(CyNC)(η 3 -P 4 C(O)tBu)] (endo-6 a) and b) exo-[(Ar*BIAN)Co(CyNC)(η 3 -P 4 C-(O)tBu)] (exo-6 a) in the co-crystal;[45] thermal ellipsoids are shown at the 50 % probability level; hydrogen atoms, disorder and non-coordinating solvent molecules are omitted for clarity. Selected bond lengths [Å] and angles [°] of endo-6 a: P1À P2 2.218(3), P1À P4 2.232(3), P2À P3 2.191(2), P3À P4 2.165(3), Co1À P2 2.3000(2), Co1À P3 2.2983(2), Co1À P4 2.3027(2), Co1À C3À N3 178.4(5); c) experimental (upward) and simulated (downward) 31 P{ 1 H} NMR spectra of endo-6 a with nuclei assigned to an AX 2 Y spin system: δ(P A ) = 144.5 ppm, δ(P x ) = 71.7 ppm, δ(P Y ) = 68.6 ppm, 1 J AX = À 318 Hz, 1 J XY = À 165 Hz, 2 J AY = À 5 Hz; exo-6 a: δ(P A ) = 50.0 ppm, δ(P M ) = 5.2 ppm, δ(P Y ) = À 26.1 ppm, 1 J AX = À 308 Hz, 1 J AM = À 207 Hz, 2 J MX = 29 Hz.…”

“…Figure 5. Solid-state molecular structures of a) [K(18c-6)][(Ar*BIAN)Co-(CN)(η 3 -P 3 )] ([K(18c-6)]8) and b) K(18c-6)][CyC(O)PCN] ([K(18c-6)]9b);[45] thermal ellipsoids are shown at the 50 % probability level; hydrogen atoms and disorder are omitted for clarity. Selected bond lengths [Å] and angles [°] of [K(18c-6)]8: P1À P2 2.1318(5), P1À P3 2.1306(5), P2À P3 2.1682(4), Co1À P1 2.3070(4), Co1À P2 2.3001(4), Co1À P3 2.3014(3), Co1À C3 1.9323(1), C1À N1 1.3211(2), C3À N3 1.1583(2), C1À C2 1.4486(2), K1À N3 2.9111(1), P1À P2À P3 59.396(2), P1À P3À P2 59.452(2), P2À P1À P3 61.152(2), Co1À C3À N3 177.83(1); [K(18c-6)]9b: P1À C1 1.7789(1), P1À C2 1.7960(1), C1À N1 1.1519(2), C2À O1 1.2397(1), P1À C1À N1 176.77(9), C1À P1À C2 95.08(5).…”