Yield:23099-21-0 55%

Reaction Conditions:

Stage #1:nipecotamide with lithium aluminium tetrahydride in tetrahydrofuran at 20; for 24 h;
Stage #2: with sodium sulfate in tetrahydrofuran

Steps:

1.1
Piperidine-3-carboxylic acid amide 1a (25 g, 0.195 mol) was added portionwise to a stirred solution of lithium aluminum hydride (14.8 g, 0.39 mol, 2.0 equiv) in dry THF (0.6 L). When the initial effervescence had subsided, the reaction was heated at reflux under N₂ at rt for 24 h. The reaction was quenched by dropwise addition of saturated sodium sulfate solution with stirring until no further effervescence was observed. The suspension was filtered through a celite plug, washed with THF (400 mL), and the filtrate concentrated under reduced pressure. The crude residue was distilled to yield pure product 1b as a colorless oil (12.4 g, 55%).

References:

Du Bois, Daisy Joe;Mao, Long;Rogers, Daniel Harry;Williams, John Patrick US2004/14775, 2004, A1 Location in patent:Page/Page column 26-27

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