Ruthenium-Mediated Cyclometalation Reactions of Allene and Allylphosphine C═C Bonds: Synthesis of κ(P),η⁴-(Hexa-2,5-dien-1-yl)diphenylphosphine–Ruthenium(II) Complexes

Abstract

The cyclopentadienyl-containing complex [Ru(η5-C5H5)(MeCN){κ3(P,C,C)-Ph2PCH2CHCH2}][PF6] (1) reacts with allenes, giving regioselectively the η2-allene complexes [Ru(η5-C5H5)(MeCN){κ(P)-Ph2PCH2CHCH2}(η2-CH2CCR1R2)][PF6] [R1 = R2 = Me (3); R1 = H, R2 = Ph (4); R1R2 = −(CH2)5– (5)]. On the other hand, the reaction of the pentamethylcyclopentadienyl-containing complex [Ru(η5-C5Me5)(MeCN){κ3(P,C,C)-Ph2PCH2CHCH2}][OTf] (2) with allenes yields regio- and stereoselectively the complexes [Ru(η5-C5Me5){κ(P),η4-Ph2PCH2CHCHC(R1R2)CHCH2}][OTf] [R1 = R2 = Me (6); R1 = H, R2 = Ph (7); R1R2 = −(CH2)5– (8)] via the intermolecular coupling of allene and allyldiphenylphosphine ligands. The intermediate complex [Ru(η5-C5Me5)(MeCN){κ(P)-Ph2PCH2CHCH2}{η2-CH2CCMe2}][OTf] (9) has been spectroscopically characterized. The structure of complex [Ru(η5-C5Me5){κ(P),η4-Ph2PCH2CHCHC(Me)2CHCH2}][{3,5-(CF3)2C6H3}4B] (6a) has been resolved by X-ray diffraction analysis.

κ3(P,C,C)-Allylphosphane Iridium(III) and Rhodium(III) Complexes: Preparation and Reactivity toward Nucleophilic Reagents

“…In the past few years, our interest has been focused on the chemistry of half-sandwich ruthenium complexes bearing allylphosphanes and we have reported the synthesis of a series of ruthenium­(II) complexes, [Ru­(η 5 -C n H m )­{κ 3 ( P , C , C )-R 2 PCH 2 CHCH 2 }­(PPh 3 )]­[X] (C n H m = C 9 H 7 , R = Ph, i Pr; C 5 H 5 , R = Ph) , and [RuCl­(η 6 -C 10 H 14 )­{κ 3 ( P , C , C )- i Pr 2 PCH 2 CHCH 2 }]­[BPh 4 ], as well as the study of their reactivity. In particular, we have focused on their usefulness in intramolecular cycloaddition reactions , and oxidative coupling reactions, as well as on their reactivity toward nucleophilic reagents toward the metallic center (ligand displacement) or the CC moiety (formation of ruthenaphosphacyclopentane complexes). , However, the coordination properties of allylphosphanes have been much less exploited in the area of rhodium and iridium chemistry. A literature search reveals that the number of half-sandwich alkenylphosphane rhodium and iridium complexes is very limited.…”

Organoruthenium Complexes Containing New Phosphorus–Carbon and Phosphorus–Carbon–Sulfur Ligands Generated in the Coordination Sphere by Nucleophilic Addition Reactions

“…The hemilabile character of alkenylphosphane ligands in ruthenium complexes has been corroborated by kinetic studies . In addition, we have approached the study of their reactivity, particularly as substrates in intramolecular cycloaddition reactions, oxidative coupling reactions, and stereoselective nucleophilic additions to afford ruthenaphosphacyclopentane complexes…”

Isomerization Processes on Organoruthenium Complexes Bearing κ2(P,C)‐Bidentate Ligands Generated Through Nucleophilic Addition to Coordinated Alkenyl Phosphanes

“…These NMR spectroscopic data agree with a highly diastereoselective generation of the chelate ring [Ru{κ 3 ( P , C , C )‐Ph 2 PCH 2 CH=CH 2 }] as reported by us for the complexes [RuCl(η 6 ‐C 10 H 14 ){κ 3 ( P , C , C )‐ i Pr 2 PCH 2 CH=CH 2 }][BPh 4 ], [Ru(η 5 ‐C 9 H 7 ){κ 3 ( P,C,C )‐Ph 2 PCH 2 CH=CH 2 }(PPh 3 )][PF 6 ],[7f] and [Ru(η 5 ‐C 5 H 5 ){κ 3 ( P,C,C )‐Ph 2 PCH 2 CH=CH 2 }(PPh 3 )][PF 6 ]. [8d]…”

“…On the other hand, hemilabile alkenylphosphane ligands are able to coordinate diastereoselectively to a metal as a chelate κ 3 ( P,C,C ), as it has been reported for some examples . This coordination mode has led to interesting reactivities involving the C‐C double bond and resulting in one single diastereoisomer …”