1-Acetyl-6-bromo-5-hydroxyindoline (Tetrahedron, 1973, 29(8), 1115) (1.24 g, 4.8 mmol), 1,2,3,5,6,8a-hexahydroindolizine-7-methanol (D2, 0.74 g, 4.8 mmol) and triphenylphosphine (1.27 g, 4.8 mmol) were stirred under Ar in dry THF (50 ml) as diethyl azodicarboxylate (0.76 ml, 4.8 mmol) was added dropwise. The mixture was stirred for 1 h, diluted with ethyl acetate, and extracted with dil. HCl. The extract was basified with potassium carbonate, and extracted with chloroform. This extract was dried (Na2SO4) and evaporated to give a dark oil. Further treatment of this oil as above with the phenol, triphenylphosphine and diethyl azodicarboxylate caused reaction to proceed further. Chromatography on silica, eluting with 0-20% methanol/dichloromethane, gave the title compound (0.25 g, 13%) as a brown gum.
