Chiral Thioaldehyde Complexes of Rhenium, X-Ray Structure Determination of [Cp(NO)(Ph3P)Re(η2-S=CHPh)]PF6 [1]
Chiral thiolate complexes [Cp(NO)(Ph3P)ReSCH2R] (R=Ph, 4-C6H4Cl, 4-C6H4OMe, H, Me) are obtained from [Cp(NO)(Ph3P)ReCH3] by acid cleavage in the presence of thiol and subsequent deprotonation. Small amounts of (chloromethyl)thioether complexes [Cp(NO)(Ph3P)ReS(CH2Cl)CH2R]BF4 are formed when dichloromethane is used as a sol vent in this reaction. Hydride abstraction using [Ph3C]PF6 converts the thiolate complexes into ionic thioaldehyde complexes [Cp(NO)(Ph3P)Re(η2-S=CHR)]PF6. These are obtained as pure (RR,SS)-diastereomers as shown spectroscopically and by X-ray structure determination of [Cp(NO)(Ph3P)Re(η2-S=CHPh)]PF6. Crystals are monoclinic, space group I2/a (No. 15), a = 25.877(3), b = 18.785(2), c = 13.768(1) Å , β = 104.93(1)°, Z -8.