Phospha-alkyne hydro-osmiation: synthesis of [Os{κ1P,κ1P′-PCRP(CHR)}Cl(CO)(PPh3)2] (R = CMe3)

Ambiphilic Reactivity of a Ruthenaphosphaalkenyl: Synthesis of P-Pyrazolylphosphaalkene Complexes of Ruthenium(0)

“…25,26 Both 4 and 5 exhibit characteristic 31 P NMR spectra, which indicate loss of the phosphaalkenic center, its resonance apparently being replaced by one in the saturated region of the spectrum (60−30 ppm) that couples to each of the, now inequivalent, PPh 3 centers. Further salient spectroscopic data include (i) 1 H NMR resonances associated with a single pz′ unit, integrating consistently against PPh 3 , (ii) appreciably shifted 1 H and 13 C resonances associated with the P−CH unit (vide infra), (iii) 1 H and 29 Si signals indicative of the retained SiMe 3 group, and (iv) a single carbonyl stretching mode (ν CO 1900 cm −1 ). The identities of 4 and 5 were ultimately established from X-ray diffraction studies, single crystals being obtained by slow cooling of saturated CH 2 Cl 2 solutions.…”

“…42 The formulation of 6 follows from spectroscopic data, 43 in comparison with related systems; thus, the P alkenyl center is significantly shifted (with respect to 3) to lower frequency (δ P 406.8) and exhibits satellite coupling to 199 Hg (J HgP = 1792 Hz), alongside a mutual interaction with the retained PPh 3 ligands (J PP = 27 Hz). Proton, carbon, and silicon spectra confirm retention of the other functionalities, while the mercury fragment is apparent from (i) a doublet resonance in the 199 Hg{ 1 H} spectrum (δ Hg −845, 1 J HgP = 1796 Hz) and (ii) the observation of Hg satellites on the 13 C resonance associated with the phenyl unit. The connectivity was ultimately confirmed by an X-ray diffraction study (Figure 2), 44 In summary, we have reported the unprecedented ambiphilic reactivity of the novel ruthenaphosphaalkenyl complex [Ru{PCH(SiMe 3 )}Cl(CO)(PPh 3 ) 2 ] (3) toward nucleophilic and electrophilic reagents, both leading to functionalization of the phosphorus center.…”

“…As with their organic counterparts, such compounds traditionally relied upon sterically encumbering or π-dative substituents (CR 2 = C(SiMe 3 ) 2 , C(NMe 2 ) 2 ; CRR′, R = SiMe 3 , R′ = Ph, R = OSiMe 3 , R′ = Mes, Ph, t Bu) to confer stability; however, with Hill and Jones’ report of [Ru(PCHR)Cl(CO)(PPh 3 ) 2 ] (R = t Bu ( 1 ), Ad ( 2 )), obtained by hydroruthenation of the respective phosphaalkynes, access to monosubstituted and unencumbered P- metallaphosphaalkenes was finally established. Nonetheless, few further analogues have been reported. − …”

Ruthenaphosphaalkenyls: Synthesis, Structures, and Their Conversion to η2-Phosphaalkene Complexes

“…Akin to the established alkyne hydroruthenation protocols, this afforded the ruthena­phospha­alkenyl [Ru­(PCH t Bu)­Cl­(CO)­(PPh 3 ) 2 ] ( 1 ), , the thiocarbonyl analogue of which was similarly obtained, alongside analogues derived from AdCP . Jones subsequently reported the successful double hydroruthenation of his bicyclo­[2.2.2]­octane-1,4-diphospha­alkyne, though Hill’s attempts to prepare an osmium analogue of 1 were thwarted by its facile incorporation of a second equivalent of t BuCP to afford a phospha­alkenyl-phospha­alkene complex …”

19 Organometallic chemistry of monometallic species

“…126 127 Reaction of [OsHCl(CO)(PPh 3 ) 2 (btd)] (btd 2,1,3-benzothiadiazole) with PC t Bu affords 22, which has both the phosphaalkenyl and phosphaalkene donors within the same metallacycle. 128 Treatment of [Fe(CCPh)(CO) 2 (Z 5 -C 9 H 7 )] with PR 3 (R i Pr or Ph) gives [Fe{=C=CPh(C 9 H 7 )}(CO) 2 (PR 3 ) 2 ] via an unexpected migration of the indenyl ligand from iron to the C b atom of the alkynyl ligand. 129 A novel method for demetallation of a series of [Fe(CO) 3 (Z 4 -diene)] complexes has been reported, using photolytically induced ligand exchange reactions with acetonitrile; the molecular structure of 23 is also described.…”