Diastereoselective Lithiation of (η6-Arene)dicarbonyltriphenylphosphane Chromium(0) Oxazoline Complexes—Direct Preparation of Enantiopure Complexes Having Planar Chiral Fragments of Either Configuration

Incorporation of a triphenylphosphane ligand is the key to the direct lithiation of (η6-2-phenyloxazoline)chromium(0) complexes. As diastereoselection can be modulated by the presence or absence of N,N,N′,N′-tetramethylethylenediamine (TMEDA), both diastereomers of 1,2-disubstituted η6-arene chromium(0) oxazoline complexes, which possess planar chiral moieties of opposite absolute configuration, can be prepared in useful chemical yields and high diastereoselectivities (10–50:1).