Asymmetric addition of Grignard reagents to cyclohexenone, catalyzed by ferrocene diphosphanes, afforded chiral magnesium enolates. These enolates reacted in a one‐pot arrangement with N‐benzylidenetoluenesulfonamide to give β‐amino carbonyl compounds with three contiguous stereocenters. Two major diastereoisomers (dr = 60:40) of product with enantioselectivities up to 95 % ee were separated by flash chromatography.

Diastereoselective ortho‐lithiation of ferrocenes is a principal strategy for the synthesis of chiral ferrocene ligands. Dilithiation of (R)‐1‐(2‐bromophenyl)‐1‐ferrocenyl‐N,N‐dimethylmethanamine leads to a dilithium intermediate, which can be transformed to a Taniaphos ligand with (R,Rp)‐configuration. On the other hand, lithiation of (R)‐1‐phenyl‐1‐ferrocenyl‐N,N‐dimethylmethanamine affords a lithiated product with opposite configuration of the stereogenic plane. Presumably, the second lithium atom attached at the ortho‐position of the phenyl ring is responsible for this difference through the intramolecular multicenter arrangement involving both lithium atoms and their adjacent carbon atoms, the iron atom of the ferrocenyl moiety, and the nitrogen atom of the amino group. This hypothesis has been supported also by quantum chemical calculations.

New planar chiral [3]ferrocenophane aminosulfane and aminophosphane ligands displayed interesting results in model Pd-catalyzed allylic substitution reactions. The phosphane derivative having a methylene group between the cyclopentadienyl ring and the phosphane group showed enantioselectivities up to 86 % ee, whereas the ligand without the

Enantioselective conjugate addition of Grignard reagents to enones, catalyzed by Cu-Taniaphos or Josiphos complex, affords chiral enolates. Ensuing one-pot Mannich reaction with TiCl(4)-generated imine leads to aminocarbonyl compounds with benzyloxycarbonyl-protected nitrogen. Both diastereomers of these compounds are isolated in moderate yields but high enantiomeric purities (up to er 97.5:2.5).

No abstract