Synthesis of Acyclic Ketones by Catalytic, Bidirectional Homologation of Formaldehyde with Nonstabilized Diazoalkanes. Application of a Chiral Diazomethyl(pyrrolidine) in Total Syntheses of Erythroxylon Alkaloids
作者:Andrew J. Wommack、Jason S. Kingsbury
DOI:10.1021/jo401377a
日期:2013.11.1
This work offers a catalytic approach to convergent ketone assembly based upon formal and tandem C–H insertion of diazoalkanes in the presence of limiting amounts of monomeric formaldehyde, which is easily generated as a gas by thermolysis of the inexpensive and abundant paraformaldehyde (∼30 USD/kg). The method forms di-, tri-, and even tetrasubstituted acetones with high efficiency, and it has streamlined
这项工作为在有限量的单体甲醛存在下,通过重氮的正式和串联C–H重氮插入而提供了一种催化酮聚合的催化方法,该单体甲醛很容易通过热解廉价而丰富的多聚甲醛而作为气体产生(约30美元/公斤)。该方法高效地形成二,三,甚至四取代的丙酮,并且简化了(-)-二氢cuscohygrine的合成过程,其中保留了脯氨酸基原料的绝对立体化学。在氧化新方案的问世帮助下,我们还提供了处理非羰基稳定的重氮化合物的完整细节。