Formaldehyde → (4-Methylmorpholin-2-yl)methyl 4-phenylpiperazine-1-carboxylate

Participants

Reaction Steps

Morpholin-2-ylmethyl 4-phenylpiperazine-1-carboxylate (non-HCl salt of Example 10; 1.00 g, 3.27 mmol) and 37% formaldehyde in water (1.97 g, 1.82 mL, 65.5 mmol) were dissolved in MeOH (20 mL) at room temperature followed by addition of sodium triacetoxyborohydride (2.78 g, 13.1 mmol) portionwise over 5 minutes. The reaction mixture was stirred for 2 h. The reaction mixture was quenched by the addition of saturated aq Na2CO3 solution. The solvents were removed in vacuo and the residual aqueous phase was loaded onto an Isolute HM-N 20 mL cartridge. The desired product was eluted with DCM (200 mL) and the solvent removed in vacuo to give (4-methylmorpholin-2-yl)methyl 4-phenylpiperazine-1-carboxylate (0.93 g, 88.9%) as a colourless gum.

Provenance & Evidence