Base-Assisted Cyclometalation and Phosphorus−Carbon Bond Cleavage in (Arene)ruthenium(II) Complexes Containing Functionalized Iminophosphorane-Phosphine Ligands Ph₂PCH₂P{NP(X)(OR)₂}Ph₂ (X = O, S; R = Et, Ph)

Abstract

Complexes [RuCl(η 6 -p-cymene)(κ 2 -P,X-Ph 2 PCH 2 P{dNP(dX)(OR) 2 }Ph 2 )][SbF 6 ] (X ) O, R ) Et (1a), Ph (1b); X ) S, R ) Et (2a), Ph (2b)) react with a stoichiometric amount of NaH, in THF at rt, to generate the neutral cyclometalated compounds [RuCl(κ 2 -P,C-Ph 2 PCHP-{dNP(dX)(OR) 2 }Ph 2 )(η 6 -p-cymene)] (X ) O, R ) Et (3a), Ph (3b); X ) S, R ) Et (4a), Ph (4b)), via selective deprotonation of the methylenic backbone of the coordinated iminophosphorane-phosphine ligands. Treatment of 3-4a,b with AgSbF 6 , in CH 2 Cl 2 at rt, affords the corresponding cationic species [Ru(κ 3 -P,C,X-Ph 2 PCHP{dNP(dX 8a), Ph (8b)) through the intramolecular O-or S-coordination of the free -Ph 2 PdNP(dX)(OR) 2 fragment. Complexes 7-8a,b can also be prepared by reaction of the dicationic derivatives [Ru(η 6 -p-cymene)(κ 3 -P,N,X-Ph 2 PCH 2 P-{dNP(dX)(OR) 2 }Ph 2 )][SbF 6 ] 2 (5-6a,b) with 1 equiv of NaH. Formation of complexes 3-4a,b and 7-8a,b proceeds, in all cases, in a diastereoselective manner. Phosphorus-carbon bond splitting has been observed upon treatment of complexes 1-2a,b, 3-4a,b, or 7-8a,b with an excess of NaH, in wet THF at rt, affording the novel phosphinito derivatives [Ru(κ 2 -C,X-CH 2 P{dNP(dX)(OR) 2 }Ph 2 ){κ 1 -P-P(dO)Ph 2 }(η 6 -p-cymene)] (X ) O, R ) Et (10a); X ) S, R ) Et (11a), Ph (11b)). Protonation and methylation of 10-11a,b generates the cationic species [Ru(κ 2 -C,X-CH 2 P{dNP(dX)(OR) 2 }Ph 2 ){κ 1 -P-P(OH)Ph 2 }(η 6 -p-cymene)][BF 4 ] (X ) O, R ) Et (12a); X ) S, R ) Et (13a), Ph (13b)) and [Ru(κ 2 -C,X-CH 2 P{dNP(dX)(OR) 2 }Ph 2 ){κ 1 -P-P(OMe)Ph 2 }(η 6 -p-cymene)][CF 3 SO 3 ] (X ) O, R ) Et (14a); X ) S, R ) Et (15a), Ph (15b)), respectively, via selective electrophilic addition at the Ph 2 PdO group. The structure of compounds [RuCl(κ 2 -P,C-Ph 2 PCHP{dNP(dO)(OPh) 2 }Ph 2 )(η 6 -p-cymene)] (3b) and [Ru(κ 2 -C,S-CH 2 P{dNP(dS)(OEt) 2 }Ph 2 ){κ 1 -P-P(dO)Ph 2 }(η 6 -C 6 H 6 )] (11a′) has been determined by X-ray crystallography.

Versatile Modes of Cooperative B−H Bond Activation Reactions in Ruthenium‐Carbene Complexes: Addition, Ring‐Opening and Insertion

“…The 11 B NMR signal appears as broad singlet at δ B =35.4 ppm and is thus almost identical to the shift reported for an osmium borylthiolato complex and the calculated NMR shift ( δ B (calcd)=28.4 ppm) of 4 . The central hydrogen atom appears as singlet (consistent with change from P V to P III ) at δ H =3.48 ppm and the corresponding carbon signal as a doublet at δ C =33.1 ppm ( 2 J PC =22.0 Hz) . All other hydrogen and carbon signals as well as their coupling constants are in the expected range for complex 4 .…”

“…[4b] The central hydrogen atom appears as singlet (consistent with change from P V to P III )a td H = 3.48 ppm and the corresponding carbon signal as ad oublet at d C = 33.1 ppm ( 2 J PC = 22.0 Hz). [17] All other hydrogen and carbon signals as well as their coupling constantsa re in the expected range for complex 4.…”

Cooperative Bond Activation Reactions with Ruthenium Carbene Complex PhSO2(Ph2PNSiMe3)C═Ru(p-cymene): Ru═C and N–Si Bond Reactivity

“…The chlorido ligand and the (freely refined) hydrogen atom of the methylene bridge adopt a cis configuration. The Ru–Cl bond length of 2.4336(5) Å is comparable to other ruthenium chlorido complexes, whereas the Ru–C bond of 2.159(2) Å is slightly shorter than in comparable methanide complexes …”

Transition metal-mediated P–C/X exchange at bound phosphine ligands (X = aryl, alkyl, NR2, OR and F): scope and mechanisms

“…In this case, a 3-membered ring is cleaved to give diphenylphosphine oxide complexes, 20. 34 A final example of P-C/O exchange involving water differs from those above as the phosphorus centre involved is not initially bound to the metal centre (see Fig. 4).…”