Synthesis
General procedure for the synthesis of tert-butyl (2-aminobenzyl)-carbamate from di-tert-butyl dicarbonate and 2-aminobenzylamine: 2-aminobenzylamine (6.0 g, 49.2 mmol) was dissolved in dichloromethane and stirred in an ice bath under nitrogen protection. A dichloromethane solution of di-tert-butyl dicarbonate (Boc)2O (10.7 g, 49.2 mmol) was added slowly and dropwise. The reaction mixture was then warmed up to room temperature to continue the reaction. After completion of the reaction, the reaction solution was washed sequentially with distilled water and saturated saline, dried over anhydrous sodium sulfate and filtered. The solvent was removed by distillation under reduced pressure and stirred overnight. The intermediate (2-aminobenzyl)-carbamic acid tert-butyl ester 5,10.5 g was obtained in 96.2% yield.
References
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