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Abstract: The effect of l-Proline as a promoter on the condensation reaction of salicylaldehyde or its derivatives with ethyl acetoacetate in neutral ionic liquid [emim]BF₄ was studied. All reactions were carried out under mild reaction conditions and achieved high yields. Moreover, the ionic liquid containing l-Proline could be recycled and reused for several times without noticeably decreasing in productivity. The results show that the l-Proline-[emim]BF₄ system has a potential in contribution to the development of environmentally friendly and inexpensive processes in organic syntheses.

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