Reactivity of Diphenylphosphino Enolato Ligands in Ruthenium(II) Complexes and Related Processes Involving Easy Cleavage of a Phosphorus−Carbon Bond in Functionalized Phosphine Ligands

Abstract

The migration of a phenyl group from phosphorus to the coordinated ruthenium center in complexes (η6-arene)[η2-Ph2PC(R)C(R‘)O]RuCl, 2 [arene = 1,3,5-Me3C6H3 or C6Me6; R = H or Me; R‘ = But], occurs in methanol at reflux. The reaction is favored by the addition of KOAc and affords selectively the stable phosphinito enolato derivatives (η6-arene)[η2-Ph(MeO)PC(R)C(R‘)O]RuPh. In contrast, the reaction of complexes 2 with methanol and K2CO3 preserves the functional ligand and affords selectively the hydride derivatives (η6-arene)[η2-Ph2PC(R)C(R‘)O]RuH. The cleavage of the ruthenium−chlorine bond in complexes 2 is also the preliminary step involved in the coupling process of functional phosphino enolato ligands with 1-alkynes HC⋮CR‘‘. The reaction results in the formation of complexes {(η6-arene)Ru[η3-CHC(R‘‘)C(R)(PPh2)C(R‘)O]}(PF6) [R = H or Me, R‘ = But or Ph, R‘‘ = H, Me, Ph, p-MeC6H4, or SiMe3], the isomerization of which into complexes {(η6-arene)Ru[η3-CH(PPh2)C(R‘‘)C(R)C(R‘)O]}(PF6), [R‘ = But, R‘‘ = H, Me, Ph, or p-MeC6H4] occurs only when R = H. The isomerization consists of an intramolecular [1,3]-migration of a phosphorus−carbon bond and is catalyzed by the fluoride anion. When R‘‘ = H, a subsequent cleavage of the ruthenium−carbon bond foreshadows the formation of (η6-C6Me6)[η1-Ph2PCH2CHCHC(O)But]RuCl2, 11. Thus, starting from the precursor (η6-C6Me6)[η1-Ph2PCH2C(O)But]RuCl2, the process achieves formally an insertion of ethyne into the starting functionalized phosphorus−carbon bond. The scarcely isolable complexes {(η6-arene)Ru[η3-C(CH2)C(R)(PPh2)C(R‘)O]Ru}(PF6) [R = H or Me, R‘ = But or Ph] reveal an easy cleavage of the functionalized phosphorus−carbon bond. This cleavage is the preliminary step involved in the formation of metallafuran complexes {(η6-arene)(Ph2PX)Ru[η2-C(CH3)CRC(R‘)O]}(PF6) [X = Cl or F, R = H or Me, R‘ = But or Ph], which implies also the capture of a halide anion by phosphorus in a transient intermediate.

Direct Preparation of [Ru(η2‐O2CO)(η6‐arene)(L)] Carbonate Complexes (L = Phosphane, Carbene) and Their Use as Precursors of [RuH2(p‐cymene)(PCy3)] and [Ru(η6‐arene)(L)(MeCN)2][BF4]2: X‐ray Crystal Structure Determination of [Ru(η2‐O2CO)(p‐cymene)(PCy3)]·1/2CH2Cl2 and [Ru(η2‐O2CO)(η6‐C6Me6Demerseman1, Mbaye2, Sémeril3 et al. 2006Eur J Inorg ChemSelf Cite465370View full textAdd to dashboardCite

“…Evidence for such a mechanism was first obtained from the study of the reaction of [RuCl(Cp)(PPh 3 ) 2 ] with NaOMe, [29] and the synthesis of [RuH(Cp)(PPh 3 ) 2 ] has since been more conveniently achieved using K 2 CO 3 in methanol. [30] The formation of the hydride derivatives 3a and 4a that occurs in methanol can be rationalised in the same way. The use of acetone as solvent precludes the formation of any ruthenium methoxide intermediate and thus allows selective formation of 2a.…”

Influence of the Polypyridyl (pp) Ligand Size on the DNA Binding Properties, Cytotoxicity and Cellular Uptake of Organoruthenium(II) Complexes of the Type [(η6‐C6Me6)Ru(L)(pp)]n+ [L = Cl, n = 1; L = (NH2)2CS, n = 2]

“…RuCl 3 ·xH 2 O and Ag(CF 3 SO 3 ) was obtained from Chempur, 1,10-phenanthroline from J. T. Baker, hexamethylbenzene, thiourea and (Me 2 N) 2 CS from Acros, and calf thymus DNA (CT DNA) from Sigma. The starting compounds [{(η 6 -C 6 Me 6 )RuCl(µ-Cl)} 2 ], [46] tap, [47] dpq, [48] dppz [49] and dppn [11] were prepared in accordance with literature procedures. All solvents were analytical reagents grade (J. T. Baker) and were dried and distilled before use.…”

Reactivity and electrochemical behavior of ruthenium dithiolene complexes with coordinatively unsaturated metal centers: cycloaddition and dimerization reactions

“…Solvents were purified by ketyl distillation before use. The precursors of complexes 1a-c, [(arene)Ru(Cl)(lCl)] 2 (arene = C 6 H 6 , C 6 H 4 (Me)(iPr) [22], C 6 Me 6 [23]), were synthesized by literature methods. Dimethyl 1,3-dithiole-2-one-4,5-dicarboxylate was obtained from the reaction of dimethyl 1,3-dithiole-2-thione-4,5-dicarboxylate (from Tokyo Kasei Kogyo Co., Ltd.) with Hg(OAc) 2 [24].…”