Phthalimide → 2-[4-(1-Diphenylmethylpiperidin-4-yl)-butyl]-isoindol-1,3-dione

Participants

Reaction Conditions

Reaction Steps

135.0 g (417 mmol) 4-(1-diphenylmethylpiperidin-4-yl)-butan-1-ol, 109.5 g (417 mmol) triphenylphosphine and 61.3 g (417 mmol) phthalimide are suspended in THF and 72.6 g (417 mmol) azodicarboxylic acid diethyl ester are added dropwise within 2½ hours under protective atmosphere and light cooling (ca. 15-25° C.). After a further hour, the solvent is removed under vacuum and the residue is crystallized three times from acetic acid ester (1000 ml, 1200 ml and 1100 ml). Colorless crystals with a MP of 150-152 were recovered. Yield 103 g (54.5%).

Provenance & Evidence