Phthalic Anhydride → HCID 22628889, compound

Participants

Reaction Steps

475.6 mg (0.50 mmol) of 8,20-bis-(4-aminobenzyl)-5,11,17,23-tetraisobutyl-2,4,10,14,16,22-hexamethyl-1,7,13,19-tetraoxa-4,10,16,22-tetraaza-cyclotetracosan-6,9,12,18,21,24-hexaone (for example from Example 4) were initially charged in 1.5 ml of glacial acetic acid and heated under reflux with 162.9 mg (1.1 mmol) of phthalic anhydride for 5 h. The mixture was concentrated, the residue was taken up in tertbutyl methyl ether (MTBE) and washed with sodium bicarbonate solution and saturated sodium chloride solution. The solution was dried with sodium sulfate, reconcentrated and subsequently filtered over a short silica gel column (Ø=3 cm, l=5 cm) using cyclohexane/ethyl acetate 2:1. Evaporation of the filtrate gave 0.55 g of slightly contaminated 8,20-bis-(4-phthalimidobenzyl)-5,11,17,23-tetraisobutyl-2,4,10,14,16,22-hexamethyl-1,7,13,19-tetraoxa-4,10,16,22-tetraaza-cyclotetracosan-6,9,12,18,21,24-hexaone as a yellow foam.

Provenance & Evidence