Stepwise Sulfuration of the Terminal Phosphido Complex trans‐[PtCl(PHCy₂)₂(PCy₂)]: Synthesis of [Pt(κ²S,S′‐PS₂Cy₂)(PHCy₂)₂]Cl and [Pt(κ²S,S′‐PS₂Cy₂){κP‐P(S)Cy₂}(PHCy₂)] and Crystal Structure of [Pt(κ²‐S,S‐PCy₂S₂)(κ‐S‐PCy₂S₂)(PHCy₂)]

Abstract

The terminal phosphido complex trans‐[PtCl(PHCy2)2(PCy2)] (1) has been prepared, exploiting the reversibility of the reaction with HCl, by action of 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) on [PtCl(PHCy2)3]Cl, and its reactivity towards elemental sulfur studied. The first product obtained by reaction of 1 with 1 equiv. of sulfur is trans‐[PtCl(PHCy2)2{κP‐P(S)Cy2}] (2), which rapidly isomerises in halogenated solvents into cis‐[PtCl(PHCy2)2{κP‐P(S)Cy2}] (3). Further addition of sulfur causes the formation of a mixture of [Pt(κ2S,S′‐PS2Cy2)(PHCy2)2]Cl (4) and [Pt(κ2S,S′‐PS2Cy2){κP‐P(S)Cy2}(PHCy2)] (5), which could be selectively synthesised; the first upon sulfuration of pure 3 and the second by reaction of 4 with 1 equiv. of sulfur in the presence of DBU. Complex 5 can be further sulfurated to [Pt(κ2S,S′‐PCy2S2)(κS‐PCy2S2)(PHCy2)] (6), which is fluxional in solution and was also characterised by single‐crystal X‐ray diffraction. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

Bridging and Terminal (Phosphanido)platinum Complexes

“…Deprotonation of [PtCl(PHCy 2 ) 3 ] + affords the dicyclohexylphosphanido complex trans ‐[PtCl(PHCy 2 ) 2 (PCy 2 )] ( 9 ), whose XRD structure is shown in Figure 1 27. Dynamic NMR spectroscopic studies revealed that 9 exhibits a dynamic process with an activation free energy (Δ G ‡ ) value of 34 kJ/mol 28.…”

“…The reactivity of the ancillary PHCy 2 ligands in 9 is shown in the sulfuration carried out with excess S 8 leading eventually to [Pt(κ 2 S , S′ ‐PCy 2 S 2 )(κ S ‐PCy 2 S 2 )(PHCy 2 )] ( 27 , Scheme ). Monitoring of the reaction showed that it proceeds stepwise, the first two S atoms attacking the terminal phosphanido P and further two S atoms attacking one of the bound PHCy 2 ligands 27…”

Why compete when you can share? Competitive reactivity of germanium and phosphorus with selenium

“…10 Metal phosphanido complexes can also react directly with elemental selenium to give phosphinoselenoite and phosphinodiselenoate complexes. [11][12][13][14] Congruent with the reactivity at phosphorus, sulfur and selenium also oxidise germanium(II) complexes to form corresponding germanium(IV) chalcogenide complexes, [15][16][17][18][19][20] although analogous reactivity with tin or lead complexes is unknown. The oxidations are driven by the formation of strong P-E or Ge-E (E = S, Se) bonds; 21 however, competing reactivity of germanium and phosphorus centres with selenium has not been reported.…”

“…This result is in contrast to previously reported oxidative reactivity between either germanium and selenium or phosphorus and selenium. [11][12][13][14][15][16][17][18][19][20] Compound 2 is the first structurally characterized example of a terminal -kSe bonding mode for the phosphinoselenoito anion, although a -kSe complex has been characterised spectroscopically. 24 The P-Se bond length [2.2602( 9) Å] is consistent with that of a single bond [2.26 Å], 12 suggesting localisation of charge on the chalcogen and a predominant contribution from the phosphinoselenoite [Cy 2 P-Se] À tautomer.…”

Solvent-Driven P–S vs P–C Bond Formation from a Diplatinum(III) Complex and Sulfur-Based Anions

“…The formation of P–S bond from coordinated diorganophosphanide and an S-based reactant is well-known. , Recently, a reversible intramolecular P–S bond formation/cleavage mediated by a Ni(0)/Ni­(II) system has been reported . However, to the best of our knowledge, all described cases result in complexes featuring a terminally bonded thiophosphane.…”