Alkyne Metathesis: Development of a Novel Molybdenum-Based Catalyst System and Its Application to the Total Synthesis of Epothilone A and C
作者:Alois Fürstner、Christian Mathes、Christian W. Lehmann
DOI:10.1002/1521-3765(20011217)7:24<5299::aid-chem5299>3.0.co;2-x
日期:2001.12.17
as 15, 16 and 20 which themselves were shown to be catalytically active. Numerous applications illustrate the performance of the catalytic system 1/CH2Cl2 which operates under mild conditions and tolerates an array of polar functional groups. The wide scope allows the method to be implemented into the total synthesis of sensitive and polyfunctional natural products. Most notable among them is a concise
通式为[Mo [(tBu)(Ar)N] 3]的受阻位钼(III)酰胺配合物,在用CH2Cl2或其他卤素供体处理后,已转变成用于各种炔烃的高效催化剂复分解反应。尽管原位形成的繁殖物种的实际性质仍然难以捉摸,但卤素转移到1的Mo中心在此类预催化剂的活化中起着决定性的作用。通过X射线晶体学可以分离和表征一些所得的卤化钼衍生物,例如15、16和20,它们本身显示出催化活性。许多应用程序说明了催化系统1 / CH2Cl2的性能,该系统在温和条件下运行并能耐受一系列极性官能团。广泛的范围使该方法可用于敏感和多官能天然产物的全合成。其中最引人注目的是简要介绍有效的抗癌药埃坡霉素A(86)和C(88)。这些目标的大环内酯核心是通过二炔113的闭环炔烃复分解(RCAM)进行锻造,然后对由此形成的环炔114进行Lindlar加氢。由于该策略打开了对(Z)-烯烃115的立体选择入口,因此该方法固有地比基于常规R