A simple and efficient method has been developed for the synthesis of symmetrical and unsymmetrical pyridines via NH4I-promoted cyclization of ketones with DMSO and NH4OAc. It was found that methyl ketones always gave selective formation of the unsymmetrical pyridine, while non-methyl ketones gave unpredictable results (symmetrical or non-symmetrical product only, or a mixture of the two). In addition
已经开发了一种简单有效的方法,用于通过
DMSO和NH 4 OAc通过NH 4 I促进的酮的环化反应来合成对称和不对称
吡啶。发现甲基酮总是选择性地形成不对称
吡啶,而非甲基酮则产生不可预测的结果(仅对称或不对称产物,或两者的混合物)。另外,
氘标记实验表明目标产物
吡啶环的C4或C6是由
DMSO产生的。