Reactivity of Heterodinuclear Complexes Formed by Platinum Insertion to Phosphorus-Bridged [1]Ferrocenophane Coordinating to a Metal Fragment

Abstract

A reaction of Pt(PMe3)4 with fcpp (fcpp = 1,1‘-ferrocenediylphenylphosphine) coordinating to CpMn(CO)2 and W(CO)5 fragments gave heterodinuclear complexes (actually they are trinuclear complexes if an iron center of a ferrocene unit is included), in which a Pt(PMe3)2 fragment was inserted into a P−C bond of the fcpp ligand to form P−Pt and η1-C5H4−Pt bonds with a μ-PPhFc bridge (μ-PPhFc = μ-PPh(C5H4FeC5H4)). X-ray analyses showed that the products were Cp(CO)2Mn(μ-PPhFc)Pt(PMe3)2 and (CO)5W(μ-PPhFc)Pt(PMe3)2, respectively. Upon a similar reaction employing Pt(PPh3)4 in place of Pt(PMe3)4, CpMn(CO)2(fcpp) gave Cp(CO)Mn(μ-CO)(μ-PPhFc)Pt(PPh3), whereas W(CO)5(fcpp) gave (CO)4W(μ-PPh2)(μ-PPh(C5H4FeC5H4Ph))Pt(PPh3), in which cleavage of a P−Ph bond of PPh3 and migration of the Ph group to a ferrocene moiety took place. To elucidate the reaction mechanism, several reaction intermediates were isolated and characterized as (CO)5W(μ-PPhFc)Pt(CO)(PPh3), cis-W- and trans-W-(CO)4(PPh3)W(μ-PPhFc)Pt(CO)(PPh3), and cis-W-(CO)4(PPh3)W(μ-CO)(μ-PPhFc)Pt(PPh3).

An organometallic tetranuclear cluster with phosphine and phosphido ligands in nonclassical bonding modes: X-ray structural characterization

“…However, 1 shows a rare case of an unsymmetrical bridging l 3 -PR 2 ligand caused by an agostic-like interaction of a P-C sp2 bond with an unsaturated palladium centre. The isolation of complexes with bridging PR 3 ligands is relevant as reaction intermediates in the syntheses of l 2 -PR 2 phosphido derivatives from the corresponding l 2 -PR 3 tertiary phosphine complexes through the oxidative addition of the P-C bond to a metal centre [53][54][55][56][57][58], as well as to rationalize the intramolecular migration of the phosphine ligands. In the same context, the interaction between the P(2)-C(37) bond and the Pd(2) centre in 1 can provide a structural model as intermediates in phosphido transfer processes and even for the syntheses of l 3 -PR phosphinidene derivatives from the corresponding l 2 -PR 2 phosphido complexes.…”

Preparation and reaction of phosphorus peri-bridged naphthalenes and their adducts with Lewis acids

“…On the other hand, several research groups and we reported that a low valent transition metal such as a zerovalent platinum complex reacts with a strained phosphaheterocyle coordinating to a metal fragment to give a ring-expanded product with a platinum fragment inserted into a P-C bond [14,15]. Thus, 7 in which 3a is coordinating to a W(CO) 5 fragment was allowed to react with Pt(PPh 3 ) 4 [7].…”

Strained Metallocenophanes and Related Organometallic Rings Containing π‐Hydrocarbon Ligands and Transition‐Metal Centers

“…[105,112] Strained phospha [1]ferrocenophanes 29 can also coordinate through the lone pair on phosphorus to metal fragments (Scheme 4), [113][114][115][116][117] which alternatively may insert into a PÀC bond (Scheme 5). [118,119] Stable phosphonium-bridged [1]ferrocenophanes, sulfurized P V derivatives, and borane adducts of (phenyl)phospha[1]-ferrocenophanes (31) have been prepared and in some cases and subjected successfully to thermal transition-metal-catalyzed ROP. [120,121] Notably, the enthalpies of thermal ROP recorded for (phenyl)phospha [1]ferrocenophane (29, R = Ph, À68 AE 5 kJ mol À1 ) [120] and (methylphenyl)phosphonium [1]ferrocenophane (31, R 1 = Ph, R 2 = Me, À61 AE 5 kJ mol À1 ) suggest slightly smaller strain energies than the typical values for dialkylsila [1]ferrocenophanes despite larger average tilt angles, though this is probably a consequence of the presence of the bulky phenyl substituent.…”