3-Chlorobenzoic Acid → HCID 58137248, compound

Participants

Reaction Conditions

Reaction Steps

2.5 M n-BuLi in hexanes (9.2 mL, 23 mmol) was added To a stirred solution of 2,2,6,6-tetramethylpiperidine (3.2 g, 23 mmol) in anhydrous THF (30 mL) at −20° C. under N2. The mixture was stirred for 1 h. at −20° C. and then cooled to −78° C. 3-Chlorobenzoic acid (1.8 g, 11.5 mmol) in anhydrous THF (20 mL) was slowly added dropwise and the mixture was stirred for 1 h at −78° C. The mixture was treated with tert-butyl 4-oxopiperidine-1-carboxylate (2.29 g, 11.5 mmol) and the resulting solution was warmed to rt and stirred overnight. The mixture was quenched with water and extracted with EtOAc (3×30 mL). The organic layers were combined, washed with brine, dried over Na2SO4, filtered and concentrated to give the crude product, which was Purified by chromatography to give tert-butyl 7-chloro-3-oxo-3H-spiro[isobenzofuran-1,4′-piperidine]-1′-carboxylate (500 mg, 13%). 1H NMR (CD3OD): δ=1.45 (s, 9H), 2.60 (m, 2H), 3.20 (b, 2H), 4.20 (b, 2H), 7.48 (m, 1H), 7.55 (m, 1H), 7.75 (m, 1H).

Provenance & Evidence