A novel 2-step synthesis of oxazole-4-carboxylates from aldehydes was developed, which is characterized by the utilization of 3-oxazoline-4-carboxylates as synthetic intermediates. The facilepreparation of 4-keto-oxazole derivatives from 3-oxazoline-4-carboxylates based on their interesting reactivity toward Grignard reagents is also described.