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Title: Phosphorus‐Atom Transfer from Phosphaethynolate to an Alkylidyne
Abstract

A low‐spin and mononuclear vanadium complex, (Menacnac)V(CO)(η2‐P≡CtBu) (2) (Menacnac=[ArNC(CH3)]2CH, Ar=2,6‐iPr2C6H3), was prepared upon treatment of the vanadium neopentylidyne complex (Menacnac)V≡CtBu(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≡CtBu)} (4), was obtained via the reaction of Na(OCP)(diox)2.5and ([ArNC(CH2)]CH[C(CH3)NAr])V≡CtBu(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≡CtBu moiety, followed by a reductive decarbonylation to form the V−C≡O linkage. The nature of the electronic ground state in diamagnetic complexes,2and4, 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 complexes2and4. This study represents the first example of a metathesis reaction between the P‐atom of [PCO]and an alkylidyne ligand.

 
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PAR ID:
10303976
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie
Volume:
133
Issue:
46
ISSN:
0044-8249
Page Range / eLocation ID:
p. 24616-24622
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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  1. Abstract

    A low‐spin and mononuclear vanadium complex, (Menacnac)V(CO)(η2‐P≡CtBu) (2) (Menacnac=[ArNC(CH3)]2CH, Ar=2,6‐iPr2C6H3), was prepared upon treatment of the vanadium neopentylidyne complex (Menacnac)V≡CtBu(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≡CtBu)} (4), was obtained via the reaction of Na(OCP)(diox)2.5and ([ArNC(CH2)]CH[C(CH3)NAr])V≡CtBu(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≡CtBu moiety, followed by a reductive decarbonylation to form the V−C≡O linkage. The nature of the electronic ground state in diamagnetic complexes,2and4, 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 complexes2and4. This study represents the first example of a metathesis reaction between the P‐atom of [PCO]and an alkylidyne ligand.

     
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