Synthesis and structure of novel triphenylarsine-substituted tungsten(0) Fischer carbene complexes

Abstract

Highlights• Structure of cis triphenylarsine-substituted tungsten(0) Fischer-type carbenes.• W-C bond trans AsPh 3 < W-C bond trans carbene < W-C bond trans CO.• Trans-influence for tetracarbonyl W(0)-carbenes: CO > PPh 3 > AsPh 3 .

Structural and electronic features of triphenylstibine-functionalized Fischer carbene complexes of molybdenum(0)

“…showed well-resolved proton signals for the carbene ligand protons. Satisfactory resolution was obtained for the signals of the proton atoms present on the 2,2'-bithienyl moiety of 4, as only the chemical shift of H14 was observed as a broad singlet, instead of an expected doublet of doublets [12,42,43]. The phenyl-ring protons of the triphenylstibine ligand were observed as a multiplet with an integration value of 15 for 1, 2, and 4, which was also reported for the triphenylphosphine [9][10][11][12] and triphenylarsine [12] analogues.…”

Molybdenum(0) Fischer ethoxycarbene complexes: Synthesis, X-ray crystal structures and DFT study

“…ligands (E = P, As) in 5 -10 and 12, due to extensive peak overlap and proton-proton coupling between the phenyl-protons [12,14]. The carbene ligand protons of the substituted tetracarbonyl complexes 5 -12 were shifted upfield compared to those of the pentacarbonyl complexes 1 -4.…”

“…The 1 H NMR spectra of 3 -12 showed well-resolved carbene ligand protons, except for H15 of 12, which was observed as a poorly-resolved multiplet. This is not uncommon for Fischer carbene complexes of 2,2'-bithiophene [14,44], and results from proton-proton coupling occurring between the protons of the 2,2'-bithienyl moiety, and peak overlap on the 1 H-NMR spectrum. Poorly-resolved multiplets were also observed for the phenyl-protons of the EPh 3…”

“…The method shown in Figure 2(a) was employed in the synthesis of 1 -12. In a prior study, the synthesis of cis-[(AsPh 3 )(CO) 4 WC(OEt)(Ar)] (Ar = 2-thienyl, 2-furyl, 2-(N-methyl)pyrrolyl or 2,2'-bithienyl) could only be achieved using hexane as solvent [14], even though the PPh 3…”

Electrochemistry of Triphenylarsine-substituted Tungsten(0) Fischer carbene complexes

“…The complexes were synthesized according to classical Fischer methodology [9,10] and literature procedures [11,12,13,14,15,16,17]. Bulk purity was confirmed with high resolution mass spectroscopy.…”