Chelating Phosphorus–An O, C, O‐Coordinating Pincer‐Type Ligand Coordinating P^III and P^V Centres

Abstract

Dedicated to Jutta Zepp on the occasion of her birthday.

Tin(ii) cations stabilized by non-symmetric N,N′,O-chelating ligands: synthesis and stability

“…These data suggest the cleavage of Et–O and iPr–O bonds accompanied by the formation of EtCl, iPrCl and Sn–O bonds to give five-membered rings (Scheme 4), in analogy with the reported formation of benzoxaphosphasiloles, 34 benzoxaphosphastannoles, 35 benzoxaphosphaplumbole, 36 and benzoxaphosphaphosphole sulfide. 37 The source of the chloride anion acting as a nucleophile in the course of the formation of 10–13 is the SnCl 3 − anion, which in turn gives SnCl 2 being complexed by a phosphorus-bound oxygen center (Scheme 4). The 31 P{H} NMR spectra of 10–13 revealed single resonances at δ = 25.6 ppm for 10 , 23.7 ppm for 11 , 9.9 ppm for 12 and 9.5 ppm for 13 .…”

“…These data suggest the cleavage of Et-O and iPr-O bonds accompanied by the formation of EtCl, iPrCl and Sn-O bonds to give five-membered rings (Scheme 4), in analogy with the reported formation of benzoxaphosphasiloles, 34 benzoxaphosphastannoles, 35 benzoxaphosphaplumbole, 36 and benzoxaphosphaphosphole sulfide. 37 The source of the chloride anion acting as a nucleophile in the course of the formation of 10-13 is the SnCl 38 The unusual reactivity of compounds 3-6 and the bonding in the newly formed neutral complexes 10-13 were the subject of the final part of the DFT investigation. The calculated ΔG value of −19 kcal mol −1 for the formation of 10-13 correlates well with the spontaneous nature of the reaction (Table S8…”

A Selective Fluorescent Optode for Lead(II) Based on the Dansylamidopropyl Pendant Arm Derivative of 1,4-Dioxa-7,13-dithia-10-azacyclopentadecane ([15]aneNS2O2)

“…Theoretical calculations were performed at the density functional theory (DFT) [31] level on Pb(II), L, [Pb(L)] 2+ , and [Pb(L) 2 ] 2 with the Gaussian 16 [32] commercial suite. Based on a previous validation carried out on strictly related compounds [33], the mPW1PW hybrid functional [34] was adopted in combination with the Ahlrichs split-valence basis sets (BSs) in the Weigend's formulation (def2SVP) [35], featuring relativistic effective core potentials (RECPs) for the heavier Pb atom. Fine numerical integration grids were adopted.…”