Proton sponge → 1-(Isocyanatomethyl)-4-(propan-2-yloxy)benzene

Beteiligte Stoffe

Reaktionsschritte

1,8-Bis(dimethylamino)-naphtalene (3.19 g, 14.9 mmol) was added to a solution of 4-(isopropoxy)phenyl acetic acid (2.89 g, 14.9 mmol) in dry tetrahydrofuran (18 mL) at rt under argon atmosphere. After 25 minutes stirring at rt diphenylphosphoryl azide (4.10 g, 14.9 mmol) was added dropwise and the mixture refluxed for 6 hours. It was allowed to cool to rt and then stored at −20° C. overnight to precipitate out the ammonium phosphate salt. A mixture of diethyl ether and ethyl acetate (1:1 v/v, 25 mL) was added to the cold reaction mixture. The precipitate was filtered from the reaction mixture and washed with diethyl ether: ethyl acetate (1:1 v/v 20 mL). The filtrate was evaporated to dryness giving 1-isocyanatomethyl-4-isopropoxybenzene as an oil (3.2 g), which was used in the next step without further purification.

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