4-Piperidinecarboxylic acid, 4-phenyl-, 4-methylbenzenesulfonate (1:1) → 4-Piperidinecarboxylic acid

Participants

Reaction Steps

To a suspension of 3.77 g (10 mmol) of 4-phenyl-4-piperidine-carboxylic acid p-toluenesulfonic acid salt (commercially available) in 31 ml of 10% Na2CO3 and 15 ml of dioxane was added at 0° C. a solution of 2.58 g (10 mmol) of fluorenylmethyl chloroformate in 20 ml of dioxane dropwise. The reacion mixture was stirred for 3 hours, diluted with 50 ml of water and extracted with EtOAc (3×20 ml). The aqueous phase was acidified with conc HCl while stirring vigorously in an ice bath. The resulting solid was collected by filtration, washed with water and dried in vacuo to provide the title compound. 1H-NMR (CDCl3, 300 MHz): 1.85 (bm, 2H); 2.50 (bm, 2H); 3.15 (bm, 2H); 3.80-4.10 (m, 2H); 4.25 (t, 1H); 4.5 (d, 2H); 7.25-7.50 (m, 9H); 7.59 (d, 2H); 7.80 (d, 2H).

Provenance & Evidence