With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.304897-49-2,tert-Butyl 4-(4-aminobenzyl)piperazine-1-carboxylate,as a common compound, the synthetic route is as follows.
In a round bottomed flask under nitrogen atmosphere commercially available benzoic acid (1.1 mmol) or sulphonyl chloride was suspended in 75 ml of anhydrous DCM. Then HOBt (1.4 mmol) and EDO HCI (1.1 mmol) were added and the resulting mixture stirred at room temperature for 2 hours. Then a solution of intermediates (X) (compounds of examples 4-6 of Table 2) (1.1 mmol) in 75 ml of dry DCM was addedand the mixture stirred at 40 00 upon completion. The reaction mixture was left to cool to room temperature, washed with a saturated aqueous solution of NH4CI, then aqueous HCI 0.5M, aqueous NaOH 1 M and finally with a saturated aqueous solution of NaHCO3. The organic layer was separated, dried over sodium sulphate, filtered and evaporated under vacuum. The resulting crude product was purified by flashchromatography on silica gel, eluting with a gradient from cyclohexane/AcOEt 1/1 to100% AcOEt. The collected fractions were evaporated to give the compounds of examples 7-10,14., 304897-49-2
As the paragraph descriping shows that 304897-49-2 is playing an increasingly important role.
Reference：
Patent; ROTTAPHARM BIOTECH S.R.L.; ARTUSI, Roberto; CASELLI, Gianfranco; ROVATI, Lucio; (78 pag.)WO2016/146220; (2016); A1;,
Piperazine – Wikipedia
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