反应详情

The crude piperazine-1,3-dicarboxylic acid-1-tert-butyl ester (4.92 mmol), prepared as described in 62(A), was suspended in dry acetonitrile (30 mL) under nitrogen atmosphere and formaldehyde (37% wt. aqueous solution, 367 mL, 4.92 mmol) and Na(OAc)3BH (2.3 g, 10.82 mmol) were added. The resulting mixture was stirred at R.T. for 3 h, then a saturated aqueous solution of NaHCO3 was slowly added until the pH was adjusted to 7. The mixture was concentrated to dryness under reduced pressure to give a yellow solid that was used without further purification for the next step.

1. concentrationThe mixture was concentrated to dryness under reduced pressure
2. customto give a yellow solid that
3. customwas used without further purification for the next step