Diisopropylethylamine → {3-[5-(4-Benzyloxy-3-ethyl-5-methyl-phenyl)-[1,3,4]oxadiazol-2-yl]-5-methyl-benzyl}-ethyl-methyl-amine

Participants

Reaction Steps

To a solution of 3-[(ethyl-methyl-amino)-methyl]-5-methyl-benzoic acid (750 mg, 3.62 mmol) in THF (10 mL), DIPEA (940 mg, 7.24 mmol) and PyBOP (1.88 g, 3.62 mmol) was added. The mixture was stirred at rt for 1 h before 4-benzyloxy-3-ethyl-5-methyl-benzoic acid hydrazide (2.06 g, 3.62 mmol) was added. The mixture was stirred at rt for 1 h and was then diluted with EA and washed with sat. aq. NaHCO3 solution. The org. phase was collected, dried over MgSO4, filtered and concentrated. The residue was dissolved in THF and Burgess reagent (1.03 g, 4.34 mmol) was added. The mixture was stirred at 110° C. under microwave irradiation for 12 min. The mixture was cooled to rt, diluted with EA and washed with water. The org. phase was separated and concentrated. The crude product is purified by CC on silica gel eluting with DCM:MeOH 9:1 to 5:1 to give {3-[5-(4-benzyloxy-3-ethyl-5-methyl-phenyl)-[1,3,4]oxadiazol-2-yl]-5-methyl-benzyl}-ethyl-methyl-amine as a pale yellow oil (1.48 g). LC-MS: tR=0.96 min; [M+1]+=456.13.

Provenance & Evidence