Phthalimide → Phenylmethyl 4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)-1-piperidinecarboxylate

Participants

Reaction Steps

A solution of DEAD (1.61 mL, 10.2 mmol) in 20 mL of THF was added to a solution of triphenylphosphine (2.69 g, 10.3 mmol), the N-Cbz-piperidine prepared in Example 16A (2.36 g, 100 mmol) and phthalimide (1.50 g, 10.2 mmol) in 80 mL of THF. After stirring 10.5 h at R.T. the mixture was quenched with water, extracted with EtOAc (3×) and the combined extracts washed with brine solution, dried over Na2SO4 and concentrated to give the crude product. Purification of this material by chromatography (hexanes/EtOAc; 2:1) gave 1.81 g, (50%) of 1-benzyloxycarbonyl-4-phthalimidylpiperidine. [1H]-NMR(CDCl3) consistent with structure.

Provenance & Evidence