Diphosphane 2,2′-binaphtho[1,8-de][1,3,2]dithiaphosphinine and the easy formation of a stable phosphorus radical cation

Abstract

A convenient synthesis route to 2,2'-binaphtho[1,8-de][1,3,2]di-thiaphosphinine () was found. Its stable radical cation 3˙(+) was accessed easily through one-electron oxidation with NOBF4.

Synthesis of bis(trithio)phosphines by oxidative transfer of phosphorus(i)

“…The singlet at ca. 50 ppm is comparable to those of other tetrathiodiphosphines reported by both Woollins 43 and Rawson 44 which feature 31 P NMR resonances in the 40 -70 ppm region and were tentatively assigned to the coupled product 1. The major product 2 at 120 ppm was more difficult to attribute.…”

“…45 It is indistinguishable from the only other reported dithiaphosphinyl dimer (2.2306(13)) and the only other example of a diphosphine bearing organosulfur substituents. 43 The P-S bond lengths We repeated the reaction with the appropriate stoichiometry (tetrathiocin:[P I dppe]Br = 1.5:2) to prevent excess [P I dppe][Br] remaining in the reaction, and monitored the reaction by 31 P NMR spectroscopy. In this case, the reaction proceeds to completion relatively quickly (within 1 -2 hours depending on the amounts of the reagents used) and affords 2 as the major product.…”

Structure–property-reactivity studies on dithiaphospholes

“…3). The P-P bond length (2.233(2) Å) is comparable with that observed in the two other crystallographically determined systems containing S 2 P-PS 2 sub-units; the one previously structurally characterised dithiaphosphole, 31 35 It should be noted that there appears to be a strong preference for dimerisation via localised P-P σ-bond formation in these systems whereas the lighter N-atom dithiazolyl analogues dimerise via multi-centre π-π interactions. This is likely a result of the superior strength of the P-P single bond (201 kJ mol −1 ) in relation to the N-N bond (167 kJ mol −1 ) coupled with stronger 2p-3p N-S π-bonding in DTAs in relation to 3p-3p P-S π-bonding in 4, i.e.…”

Structure and Reactivity of 1,8-Bis(naphthalenediyl)dipnictanes

“…Our interest in the structure , and reactivity of dipnictanes R 4 E 2 (E = Sb, Bi), which has led to the synthesis of group 13/15 − and group 15/16 compounds, − prompted our attention to 1,8-naphthalenediyl-substituted (Naph) derivatives. Peri -substituted complexes of group 15 (type I ) − and group 16 elements − as well as mixed group 15/16 compounds − are known (Scheme ), and pnictogen–pnictogen as well as chalcogen–chalcogen interactions have been studied to some extent. Recently, we reported the synthesis of distibane Naph 2 Sb 2 2 (type III ), which was formed by reductive coupling of two Sb­(III) centers as was observed in the reaction of 1,8-dilithionaphthalene NaphLi 2 with PhPCl 2 , yielding Naph­(PPh) 2 (type II ) .…”