2-Phthalimidoacetaldehyde Diethyl Acetal → Phthalylglycine aldehyde

Participants

Reaction Conditions

Reaction Steps

Phthalimidoacetaldehyde diethyl acetal (75 g, 284.8 mmol) was added in one portion to 450 mL of 2N HCl in a 1 L 3-necked round bottom flask equipped with mechanical stirring. The suspension was heated to 70° C. By the time the internal temperature reached 70° C., the reaction mixture was clear and starting material was consumed as determined by HPLC. The reaction mixture was stirred at 70° C. for 30 minutes. The reaction mixture was allowed to cool to ambient temperature with stirring overnight, at which time the solid product had precipitated. The reaction was diluted with 400 mL of water and mixed for 3 hours. The solid was filtered and washed with 1 L of water, air dried, and dried in a vacuum oven at ambient temperature with a nitrogen bleed to afford the title compound (46.5 g, 86.4% yield). 1H NMR (CDCl3): δ 9.65 (s, 1 H), 7.94 (m, 2 H), 7.75 (m, 2 H), 4.58 (s, 2 H).

Provenance & Evidence