p-Toluenesulfonic acid → 3-[5-(Phenylmethyl)-1,2,4-oxadiazol-3-yl]propanal

Participants

Reaction Steps

Crude 3-[3,3-bis(ethyloxy)propyl]-5-(phenylmethyl)-1,2,4-oxadiazole (5.63 g, 19.4 mmol) in EtOH (75 ml) was stirred with p-toluenesulphonic acid (0.738 g, 3.9 mmol) for 21 h and the mixture partitioned between EtOAc and water. The organics were isolated washed with water and brine, dried and concentrated to a red oil. This material contained significant amounts of acetal, therefore the oil was dissolved in THF (15 ml) and treated with 2M HCl solution for 2 h then partitioned between EtOAc and water. The organics were isolated washed with brine, dried and concentrated to yield 3-[5-(phenylmethyl)-1,2,4-oxadiazol-3-yl]propanal as a red/brown oil (3.77 g) which was used crude in the next stage.

Provenance & Evidence