Acetic acid, 2-(triphenylphosphoranylidene)-, methyl ester → 1,2-dibenzyl 3-tert-butyl (2S,3S)-5-(2-methoxy-2-oxoethylidene)piperidine-1,2,3-tricarboxylate

Beteiligte Stoffe

Reaktionsschritte

To an oven-dried 25 mL round-bottomed flask equipped with a magnetic stir bar and under a nitrogen gas atmosphere was placed methyl(triphenylphosphoranylidene)acetate (199 mg, 0.597 mmol) and toluene (5 mL). To this heterogeneous solution was added a solution of 1,2-dibenzyl 3-tert-butyl(2S,3S)-5-oxopiperidine-1,2,3-tricarboxylate (93 mg, 0.199 mmol) in toluene (3 mL). The reaction mixture was heated to reflux and stirred overnight. The volatiles were then removed in-vacuo and the yellow oil was purified by Combiflash (10 to 30% ethyl acetate in hexanes) to afford 83 mg (80%) of 1,2-dibenzyl 3-tert-butyl(2S,3S)-5-(2-methoxy-2-oxoethylidene)piperidine-1,2,3-tricarboxylate. LCMS (ESI): 424 (M-CO2t-Bu+2H+), 468 (M-t-Bu+2H+), 524 (M+H+).

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