Triethylamine → HCID 69652394, compound

Participants

Reaction Steps

Add resin-bound tetrabutylammonium fluoride (TBAF) (22 g, 22.0 mmol, 1.6 mmol F/gram) to a solution of 5-(2-trimethylsilanyl-ethoxycarbonylamino)-piperidine-1,3-dicarboxylic acid 1-tert-butyl ester 3-ethyl ester (4.63 g, 11.0 mmol) in THF (150 mL). Reflux 48 H, cool to room temperature and concentrate to dryness. Dissolve in CHCl3. Wash 2× sat. aq NaHCO3, wash 2× brine, dry over Na2SO4, filter, and concentrate to dryness. Add Et3N (4.6 mL, 33.0 mmol) and DMAP (5 mg, cat.) to a solution of the residue (3.0 g, 11.0 mmol) in CH2Cl2 (100 mL). Add 3-(2-chloro-6-fluoro-phenyl)-3-methyl-isoxazole-4 carbonyl chloride (4.3 g, 15.4 mmol, Great Lakes Chemical) and stir overnight at room temperature. Add CHCl3. Wash 2× with sat. aq NaHCO3, wash 2× with brine, dry over Na2SO4, filter and concentrate to dryness. Purify by column chromatography using EtOAc/hexanes as eluant and concentrate to dryness to yield the title compound (2.6 g, 46%) as a yellow foam as a mixture of cis isomers. MS(IS) 510.2 (M+); Anal. Calc'd for C24H29ClFN3O4.0.05CHCl3: C, 55.99; H, 5.68; N, 8.14. Found: C, 55.91; H, 5.72; N, 8.03.

Provenance & Evidence