The synthesis of a new bis(oxazoline) ligand from D-glucosamine and its application in enantioselective copper(I) catalysed cyclopropanations of olefins is described.

A new type of carbohydrate-based bis(oxazoline) ligands was prepared from inexpensive D-glucosamine and tested in asymmetric cyclopropanation reactions. For optimisation, modified ligands with 3-O substituents of varying size and electronic properties were prepared as well as a 3-OH unprotected and a perpivaloylated derivative. All new ligands were tested in asymmetric cyclopropanation, revealing a strong dependence of enantioselectivity on steric demand

A new carbohydrate-based pyridyl bis(oxazoline) has been prepared from d-glucosamine via simple steps. With this ligand enantioselectivities up to 99% were achieved in copper(I)-catalysed alkynylations of imines.

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