Optically Active Transition Metal Complexes. 128 [1] Synthesis,Characterization and Molecular Structures of Cycloheptatrienyl‐Iminphos‐Molybdenum Complexes Differing Only in the Metal Configuration

The chiral‐at‐metal cycloheptatrienyl‐molybdenum complexes (R_Mo, S_C)‐(η⁷‐C₇H₇)Mo(iminphos)(CO)]BF₄ ( 2a ) and (S_Mo, S_C)‐(η⁷‐C₇H₇)Mo(iminphos)(CO)]BF₄ ( 2b ) (iminphos = 2‐N‐(S)‐1‐phenylethylcarbaldimino]phenyl(diphenyl)phosphane), which only differ in the molybdenum configuration, were prepared and separated by fractional crystallization. The absolute configuration for both diastereomers was determined by X‐ray analysis. ¹H NMR studies demonstrated the configurational lability at the molybdenum centre in solution.