Decarbonylation along with P‐atom transfer from the phosphaethynolate anion, PCO−, to the NbIVcomplex [(PNP)NbCl2(N
Decarbonylation along with P‐atom transfer from the phosphaethynolate anion, PCO−, to the NbIVcomplex [(PNP)NbCl2(N
- NSF-PAR ID:
- 10443436
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie
- Volume:
- 134
- Issue:
- 52
- ISSN:
- 0044-8249
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract A low‐spin and mononuclear vanadium complex, (Menacnac)V(CO)(η2‐P≡C
t Bu) (2 ) (Menacnac−=[ArNC(CH3)]2CH, Ar=2,6‐i Pr2C6H3), was prepared upon treatment of the vanadium neopentylidyne complex (Menacnac)V≡Ct Bu(OTf) (1 ) with Na(OCP)(diox)2.5(diox=1,4‐dioxane), while the isoelectronic ate‐complex [Na(15‐crown‐5)]{([ArNC(CH2)]CH[C(CH3)NAr])V(CO)(η2‐P≡Ct Bu)} (4 ), was obtained via the reaction of Na(OCP)(diox)2.5and ([ArNC(CH2)]CH[C(CH3)NAr])V≡Ct Bu(OEt2) (3 ) in the presence of crown‐ether. Computational studies suggest that the P‐atom transfer proceeds by [2+2]‐cycloaddition of the P≡C bond across the V≡Ct Bu moiety, followed by a reductive decarbonylation to form the V−C≡O linkage. The nature of the electronic ground state in diamagnetic complexes,2 and4 , was further investigated both theoretically and experimentally, using a combination of density functional theory (DFT) calculations, UV/Vis and NMR spectroscopies, cyclic voltammetry, X‐ray absorption spectroscopy (XAS) measurements, and comparison of salient bond metrics derived from X‐ray single‐crystal structural characterization. In combination, these data are consistent with a low‐valent vanadium ion in complexes2 and4 . This study represents the first example of a metathesis reaction between the P‐atom of [PCO]−and an alkylidyne ligand. -
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