Cyclometallation of phenylphosphine and neopentyl ligands in ruthenium(II) complexes: synthesis and crystal structure of the orthometallated complexes [Ru(C6H4PR1R2)(CH2CMe3)(η6-C6Me6)](R1= R2= Ph; R1= Me, R2= Ph; R1= R2= Me) and of the metallacyclobutanes [Ru(CH2CMe2CH2)(η-C6Me6)(PPhR1R2)](R1= R2= Ph; R1= Me, R2= Ph)

Abstract

The compounds [RuCl₂(η⁶-C₆Me₆)L](L = PPh₃1, or PMePh₂2) react with an excess of Mg(CH₂CMe₃)Cl to give the corresponding orthometallated complexes [[graphic omitted]R¹R²)(CH₂CMe₃)(η⁶-C₆Me₆)][R¹= R²= Ph, 4; R¹= Me, R²= Ph, 5, only the diastereomer (RS:SR)], and the metallacyclobutanes [[graphic omitted]H₂)(η⁶-C₆Me₆)(PPhR¹R²)](R¹= R²= Ph, 7; R¹= Me, R²= Ph, 8). In contrast [(RuCl₂(η⁶-C₆Me₆)(PMe₂Ph)]3 reacts to give only the orthometallated complex [[graphic omitted]Me₂)(CH₂CMe₃)(η⁶-C₆Me₆)]6. The X-ray crystal structures of complexes 4–8 have been determined and their conformations are discussed. Crystal data are: 4, a= 10.483(2), b= 16.050(10), c= 18.451(9)Å, β= 103.65(4)°, Z= 4, space group P2₁/c, R= 0.0548; 5, a= 11.926(3), b= 17.810(5), c= 12.780(3)Å, β= 99.37(1)°, Z= 4, space group P2₁/c, R= 0.0480; 6, a= 16.762(21), b= 10.116(10), c= 14.874(15)Å, β= 108.08(5)°, Z= 4, space group P2₁/n, R= 0.0441; 7, a= 10.720(20), b= 11.670(20), c= 12.050(10)Å, α= 80.32(4), β= 78.60(10), γ= 87.88(3)°, Z= 2, space group P, R= 0.0232; 8, a= 8.842(10), b= 8.898(20), c= 17.840(70)Å, α= 92.91(6), β= 102.48(50), γ= 103.12(9)°, Z= 2, space group P, and R= 0.0529.