To a 100 mL round-bottomed flask equipped with stirring was added 2-nitrophenyl boronic acid (Combi-Blocks Chemical Company) (210 mg, 1.3 mmol), LiCl (Aldrich) (168 mg, 4 mmol), tetrakis(triphenyl-phosphine)palladium (O) (Strem Chemical Company) (69 mg, 0.06 mmol) and tert-butyl 4-[(trifluoromethyl)-sulfonyloxy]-1,2,5,6-tetrahydro-pyridinecarboxylate [prepared by the method of Wustrow, D. J. and Wise, L. D., Synthesis 1991, 993-995, from tert-butyl-4-oxopiperidine-1-carboxylate (Aldrich), LDA (Aldrich) and N-phenyltrifluoromethancsulfonimide (Aldrich)] (397 mg, 1.2 mmol) in DME (5 mL). The reaction mixture was purged with N2 and a 2 M soln of Na2CO3 (1.8 mL, 3.6 mmol) was introduced. After heating the mixture to 90° C. for 3 h, the reaction was cooled to 25° C. and diluted with EtOAc (15 mL). The organic layer was separated, washed with 10% Na2CO3, H2O and satd NaCl and dried over Na2SO4, filtered and concentrated in vacuo to afford a dark yellow oil. The crude material was purified by column chromatography (3:1 hexane:EtOAc) to give the title compound as a white solid (240 mg). MS (ESI, pos. ion) m/z: 305 (M+1). Calc'd for C16H20N2O4: 304.34.
