Oxidation of Thioether Ligands in Pseudotetrahedral Cyclopentadienylruthenium Complexes: Toward a New Stereoselective Synthesis of Chiral Sulfoxides(1).

Ionic ruthenium thioether complexes [Cp(LL‘)Ru(SRR‘)]PF6 (LL‘ = Ph2PCH2PPh2 (1), Ph2PC2H4PPh2 (2), (Ph3P, CO) (3), Me2PC2H4PPh2 (4), (S,S)-Ph2PCHMeCHMePPh2 (5), SRR‘ = MeSPh (a), MeS-i-Pr (b), MeSBz (c), i-PrSBz (d), EtSBz (e), MeSCy (f), SC4H8 (g)) were synthesized from the corresponding chloro complexes [Cp(LL‘)RuCl] and thioethers. 5a crystallized in the orthorhombic system, space group P212121 (No. 19), with a = 11.269(3) A, b = 15.104(2) A, c = 23.177(4) A, and Z = 4. 5b crystallized in the monoclinic system, space group P21 (No. 4), with a = 10.539(5) A, b = 16.216(9) A, c = 11.011(8) A, β = 106.04(2)°, and Z = 2. A similar ligand exchange reaction yielded the analogous sulfoxide complexes [Cp(LL‘)Ru(S(O)RR‘)]PF6 (6−10). 10a crystallized in the orthorhombic system, space group P212121 (No. 19), with a = 14.1664(13) A, b = 15.792(2) A, c = 17.641(2) A, and Z = 4. 10b·0.93CH2Cl2 crystallized in the orthorhombic system, space group P212121 (No. 19), with a = 12.069(2) A, b = 17.379(2) A, c = 19.760(5) ...