p-Toluenesulfonyl azide → (4-Cyclopropanesulfonyl-phenyl) diazo acetic acid ethyl ester

Participants

Reaction Steps

Ethyl 2-(4-cyclopropylsulfonylphenyl)acetate [obtained as described in WO2004/072031 (40 g, 149.07 mmol)] was dissolved in dry acetonitrile (745 mL) under argon atmosphere. To the above solution para toluene sulfonyl azide (32.33 g, 163.97 mmol) was added, followed by DBU (33.40 mL, 223.6 mmol) in dropwise manner, and stirred for 30 min. Reaction mixture was poured in ice cold water (500 mL), solid obtained was filtered through buchner funnel and dried under vaccum which yielded ethyl 2-(4-cyclopropylsulfonylphenyl)-2-diazo-acetate (40 g).

Provenance & Evidence