Characterization, Reactivity, and Potential Catalytic Intermediacy of a Cyclometalated Tri-tert-butylphosphine Palladium Acetate Complex

Abstract

b S Supporting Information ' ASSOCIATED CONTENT b S Supporting Information. NMR spectra and X-ray crystallographic data (in CIF format) are available free of charge via the Internet at http://pubs.acs.org.

Isolation and Catalytic Reactivity of Mononuclear Palladium(I) Complexes

“…4A). 33 The Pd-P and Pd-C bond lengths and the P1-Pd1-C1 bite angle for the cyclometalated phosphine are comparable to the previously reported cyclometalated Pd II complexes [(P t Bu3)Pd(κ 2 P,C-P t Bu2CMe2CH2)(OAc)]HOAc 45 and [Pd(κ 2 P,C-P t Bu2CMe2CH2)(P t Bu3)](PF6). 46 The formation of complex Pd-5 was also confirmed by its independent synthesis and NMR and X-ray characterization from the cyclometalated Pd II precursor (Figs.…”

“…S10-S12). Notably, there are only a few examples of other similar mononuclear cyclometalated Pd II complexes, [45][46][47] and to the best of our knowledge formation of Pd-5 is the first example of an intramolecular C-H bond activation that likely proceeds at a Pd I center. In 2016,…”

One‐Electron Oxidation of [M(PtBu3)2] (M=Pd, Pt): Isolation of Monomeric [Pd(PtBu3)2]+ and Redox‐Promoted C−H Bond Cyclometalation

“…Motivated by the cyclometalation observed on oxidation of 1 b , we have also preliminarily investigated whether similar reactivity can be induced in the palladium analogue. Our studies are on‐going, but we do note that reaction of 1 a with two equiv of [Fc][PF 6 ] in the presence of excess 2,6‐bis(decyl)pyridine (5 equiv) resulted in the gradual appearance of a diamagnetic complex with spectroscopic characteristics consistent with cyclometalation ( 3 a ; δ ( 31 P) 57.0, −1.3 ppm; 2 J PP =316 Hz) . However, this species was only formed in situ in about 30 % yield after 72 h at 293 K, as measured by NMR spectroscopy (using an internal standard), and the resulting reaction mixture has proved intractable so far to further characterization.…”

Isolation and Catalytic Reactivity of Mononuclear Palladium(I) Complexes

“…37 The Pd-P and Pd-C bond lengths and the P1-Pd1-C1 bite angle for the cyclometalated phosphine are comparable to the previously cyclometalated Pd II complex [(P t Bu3)Pd(CH2C(CH3)2P t Bu2)(OAc)]HOAc. 43 Notably, there are only a few examples of other similar mononuclear cyclometalated Pd II complexes, [43][44][45] and to the best of our knowledge formation of Pd-5 is the first example of an intramolecular C-H bond activation that likely proceeds at Pd I center. was provided for such a cyclometalated Pd II complex.…”