tert-butyl N-[2-[2-(2-hydroxyethoxy)ethoxy]ethyl]-N-methylcarbamate

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 8-[2-(4-tert-Butoxycarbonyl-2-methyl-phenyl)-ethanesulfonyl]-2-(3-hydroxy-5-trifluoromethyl-phenyl)-4-oxo-1,3,8-triaza-spiro[4.5]dec-1-ene-3-carboxylic acid tert-butyl ester (30.0 mg, 43.1 μmol), {2-[2-(2-hydroxy-ethoxy)-ethoxy]-ethyl}-methyl-carbamic acid tert-butyl ester (22.7 mg, 86.2 μmol) and triphenylphosphine (22.6 mg, 86.2 μmol) were dissolved in THF (0.22 mL). TMAD (14.8 mg, 86.2 μmol) was added and the mixture was stirred at 60° C. for 30 minutes in a nitrogen atmosphere. The reaction solution was concentrated under reduced pressure, and the resulting residue was then purified by silica gel column chromatography (hexane-ethyl acetate) to give 2-[3-(2-{2-[2-(tert-butoxycarbonyl-methyl-amino)-ethoxy]-ethoxy}-ethoxy)-5-trifluoromethyl-phenyl]-8-[2-(4-tert-butoxycarbonyl-2-methyl-phenyl)-ethanesulfonyl]-4-oxo-1,3,8-triaza-spiro[4.5]dec-1-ene-3-carboxylic acid tert-butyl ester (37.4 mg, 86%). The reaction solution was concentrated under reduced pressure the resulting residue was then purified by silica gel column chromatography (hexane-ethyl acetate)