A selective method for the synthesis of substituted and annulated pyrano[2,3-d]pyrimidines consisting in acylation of 2-amino-3-cyano-4H-pyrans with acetic anhydride has been developed. It was shown for the first time that acid catalysis is more efficient in this reaction, rather than base catalysis as it has been believed earlier.
研究人员开发了一种选择性合成取代和环化
吡喃并[2,3-d]
嘧啶的方法,该方法包括用
乙酸酐对 2-
氨基-3-
氰基-
4H-吡喃进行酰化。研究首次证明,在这一反应中,酸催化比碱催化更有效。