NCN‐Chelated Organoantimony(III) and Organobismuth(III) Phosphonates: Syntheses and Structures

Abstract

The reactions of the organoantimony and organobismuth oxides

NCN Chelated Organoantimony(III) and Organobismuth(III) Phosphinates and Phosphites: Synthesis, Structure and Reactivity

“…As a part of an ongoing investigation of main group compounds containing potentially tridentate pincer-type ligands, and as a logical continuation of studies in this field, we report herein the syntheses, structures and reactivity of organoantimony and organobismuth phosphinate and phosphite complexes (Scheme 1) that are stabilized by the NCN chelating ligand L. Previously we were able to synthesize mixed phoshonate compounds (i.e. complexes containing two different phosphonate groups), [3] and herein the syntheses of novel mixed phosphinate-phosphite, phosphonate-phoshinate and phosphonate-phosphite compounds are also described (Scheme 2). Scheme 2.…”

“…Both compounds 5 and 6 contain POH groups in their structure, which was reflected by observation of three broad bands (around 2700, 2300 and 1600 cm -1 ) in their IR spectra, and splitting of the POH peaks points to strong hydrogen bonds between these POH moieties. [3,5] We have recently reported so-called mixed antimony(III) and bismuth(III) phoshonates, in which two different phosphonate units are bonded to the same central ion. [3] We have also suggested that an analogous synthetic protocol may lead to similar phosphorus-antimony(bismuth) compounds containing either two phosphorus ions in a +III oxidation state, or with one phosphorus ion in a +III state and the other in a +V state.…”

“…[3,5] We have recently reported so-called mixed antimony(III) and bismuth(III) phoshonates, in which two different phosphonate units are bonded to the same central ion. [3] We have also suggested that an analogous synthetic protocol may lead to similar phosphorus-antimony(bismuth) compounds containing either two phosphorus ions in a +III oxidation state, or with one phosphorus ion in a +III state and the other in a +V state. Compound 7 showed a propensity to react with acids, as demonstrated by a 1 H and 31 P NMR experiment, and when mixed with 2 equiv.…”

“…We have also demonstrated that these NCN chelated organoantimony(III) and organobismuth-(III) oxides can be utilized as starting materials for the controlled and reliable preparation of organometallic molecular phosphonates. [3] In this way, we enriched the available knowledge of similar group 15 compounds, which is at this time still quite limited. [4] Studies dealing with this class of Scheme 1. compounds are often hampered by their limited solubility.…”

“…With phosphonate 10 [3] as a starting compound the mixed phosphonate-phosphite compounds 11 and 12 can be prepared, depending on which reagent is added, namely, phenylphosphinic or phosphorous acid (Scheme 2). The 1 H and 13 C NMR spectra of 11 and 12 are consistent with the proposed structures.…”