Tributylphosphine → 3-{4-[2-(4-Chloro-phenyl)-7-oxo-4,7-dihydro-5H-thieno[2,3-c]pyridin-6-yl]-2-methoxy-phenoxy}-azetidine-1-carboxylic acid tert-butyl ester

Participants

Reaction Steps

Dissolve 3-(4-{[5-(4-chloro-phenyl)-3-(2-hydroxy-ethyl)-thiophene-2-carbonyl]-amino}-2-methoxy-phenoxy)-azetidine-1-carboxylic acid tert-butyl ester (840 mg, 1.50 mmol) and tri-n-butylphosphine (2.25 mmol, 562 μL) in tetrahydrofuran (15 mL) and add slowly dropwise diisopropyl azodicarboxylate (2.25 mmol, 447 μL). Stir the mixture overnight and concentrate in vacuo. Triturate the residue with Et2O, filter, and dry in vacuo to afford 550 mg (62%) of the title compound as a white solid. LC-MS/ES m/z (35Cl) 441.0 [M-tBuCO2+H]+.

Provenance & Evidence