Structural, far-IR and phosphorus-31 NMR studies of two-coordinate complexes of tris(2,4,6-trimethoxyphenyl)phosphine with silver(I) halides

A Dinuclear Gold(I)–Silver(I) Derivative of 2‐Cyclopentylidene‐2‐sulfanylacetic Acid and Related Complexes: Synthesis, Crystal Structures, Properties and Antitumor Activity

“…[44] and references cited therein) for triphenylphosphane complexes containing silver(I) with a coordination number Յ 3. [42,44,45] The spectrum re- was detected, and the δ and 1 J values indicate the existence of a unique environment for the silver(I) atom with a tetrahedral geometry. The room-temperature 31 P{ 1 H} NMR spectra in the solvents used (see Table S1, Supporting Information) each contain a single signal for the two PPh 3 ligands, which are more shielded than those in compound 3.…”

“…At a temperature of 213 K, the low-field peak appeared as a singlet at δ = 36.2 ppm, but the high-field signal was split into the characteristic doublet of doublets due to the coupling of the P nucleus with the two Ag natural isotopes, centred at δ = 14.3 ppm (Figure 8). [42,44,45] The behaviour of compound 4 in solution is more complicated. The 1 J31 P, 109,107 Ag values of 672 and 582 Hz are comparable to those reported in the literature (ref.…”

BR2BodPR2: highly fluorescent alternatives to PPh3and PhPCy2

“…The observation of Ag-P coupling at room temperature was unusual since the rapid exchange of the phosphine ligands usually causes this coupling to be averaged to zero; this ligand exchange is normally slowed down by cooling the solution to low temperatures (as is the case for 6a and 6b). 27 However, the observation of Ag-P coupling at room temperature has been reported previously, where the phosphine is sterically hindered or chelating. 27,31 Phosphines 3a and 3b are also bulky which may explain the lower rate of phosphine exchange and the observation of Ag-P coupling.…”

“…27 However, the observation of Ag-P coupling at room temperature has been reported previously, where the phosphine is sterically hindered or chelating. 27,31 Phosphines 3a and 3b are also bulky which may explain the lower rate of phosphine exchange and the observation of Ag-P coupling. The electrospray mass spectra gave peaks for [M − (hfa)] + at m/z of 1489.7998 for 7a, and 1242.7354 for 7b.…”

“…For these signals the following Ag-P couplings were measured: 1 J 107AgP = 696 Hz and 1 J 109AgP = 803 Hz, and 1 J 107AgP = 590 Hz and 1 J 109AgP = 677 Hz for 6a and 6b respectively. The increase in Ag-P coupling constants indicates a change in the hybridisation state of the silver(I) complex 26, 27 and is attributed to [Ag-(2a/2b)(hfa)] with only one phosphine ligand bound. The coupling constants are similar to the reported values for [Ag(PR 3 )-(hfa)] (R = Ph, Me, Et): 1 J 107AgP = 700-760 Hz.…”