Synthesis and crystal structure of [Ru(η5-C5H4CH4CH2PPh2)(PPh3)Cl], a compound having a cyclopentadienyl proton with a chemical shift of δ 1.91 p.p.m.

Abstract

The room-temperature ¹H n.m.r. spectrum of [[graphic omitted]Ph₂)(PPh₃)(Cl](1) in [²H₈]toluene contains a cyclopentadienyl resonace at δ 2.29; upon cooling to –60 °C this moves to δ 1.91. This high-field chemical shift is ascribed to the shielding effect of the aromatic ring current of a phenyl ring of the PPh₃ ligand. The X-ray crystal structure of (1) is reported; the crystals are orthorhombic, space group Pc2₁n with a= 10.161(2), b= 15.735(3), c= 19.256(5)Å, and Z= 4. The structure was solved via the heavy-atom method and refined to R= 0.028 using 2137 independent reflections. Reaction of compound (1) with trimethyl phosphite gives [[graphic omitted]Ph₂){P(OMe)₃}Cl](2) and with AgBF₄ and (+)-PhCH(Me)NH₂ yields the diastereoisomers of [[graphic omitted]Ph₂)(PPh₃){(+)-NH₂CH(Me)Ph}]BF₄(3).