The scope and limitations of the platinum catalyzed 7-endo cyclization of internal alkynyl amides were investigated. Substitution of the alkyne with an aryl group gave better results, presumably because it stabilized the transition state. Applying the reaction to a secondary amide, the caprazamycin core was successfully synthesized from commercially available material in eight steps.
研究了
铂催化的内烃乙酰胺7-内环化的范围和局限性。用芳基取代
炔烃得到了更好的结果,这可能是因为它稳定了过渡态。将此反应应用于二级酰胺,成功地从商业可获得的材料合成了卡帕霉素核心,历时八步。