[CH:1]1([CH2:7][CH:8]([C:12]([O:14][CH2:15][CH3:16])=[O:13])[C:9](O)=[O:10])[CH2:6][CH2:5][CH2:4][CH2:3][CH2:2]1.C(Cl)(=O)C([Cl:20])=O>C(OCC)(=O)C.CN(C=O)C>[Cl:20][C:9]([CH:8]([CH2:7][CH:1]1[CH2:6][CH2:5][CH2:4][CH2:3][CH2:2]1)[C:12]([O:14][CH2:15][CH3:16])=[O:13])=[O:10]A solution comprised of 3-cyclohexyl-2-ethoxycarbonylpropionic acid (8.52 g, 37 mmol) in ethyl acetate (80 mL) was cooled to 0° C. was treated sequentially with 2 drops of DMF and oxalyl chloride (3.93 mL) added dropwise over five minutes. The mixture was allowed to warm slowly and after approximately 2 hours concentrated to provide ethyl 2-chlorocarbonyl-3-cyclohexylpropionate.
Wird geladen…