To 13 mg (0.10 mmol) 6-methoxy-pyridin-2-ol in THF (1.0 mL) is added 23 mg (0.10 mmol) (S)—N-{1-[4-(3-hydroxy-azetidin-1-yl)-phenyl]-ethyl}-acetamide (V.1) in THF (1.0 mL). 29 mg (0.11 mmol) triphenylphosphine and 25 mg (0.11 mmol) di-tert-butyl azodicarboxylate are added and the mixture is stirred for 3 h at 60° C. Another portion of 29 mg (0.11 mmol) triphenylphosphine and 25 mg (0.11 mmol) di-tert-butyl azodicarboxylate are added and stirring is continued for 2 h at 60° C. The mixture is concentrated in vacuo and the residue is purified by HPLC (XBridge, acetronitrile/H2O (+0.1% NH4OH)) to yield the desired product.
