Département de chimie moléculaire

Ruthenacycles, which are easily prepd. in a single step by reaction between enantiopure arom. amines and [Ru(arene)Cl2]2 in the presence of NaOH and KPF6, are very good asym. transfer hydrogenation catalysts. A range of arom. ketones were reduced using isopropanol in good yields with ee's up to 98{%}. Iridacycles, which are prepd. in similar fashion from [IrCp*Cl2]2 are excellent catalysts for the racemization of secondary alcs. and chlorohydrins at room temp. This allowed the development of a new dynamic kinetic resoln. of chlorohydrins to the enantiopure epoxides in up to 90{%} yield and 98{%} enantiomeric excess (ee) using a mutant of the enzyme Haloalc. dehalogenase C and an iridacycle as racemization catalyst. [on SciFinder(R)]