1-Bromo-2-iodoethylene (9) was used as a central, pseudosymmetric building block for the fully convergent and modular synthesis of two related natural products, cis (1a) and trans (1b) bupleurynol. In doing so, a 9-step synthesis of 1a (reported previously) has been vastly truncated to one single operation by using queued cross-coupling reactions with Pd catalysis, negating the need for any protecting
                                    1-溴-2-碘乙烯(9)被用作中央,假对称的构建基块,用于完全收敛和模块化合成两种相关的
天然产物,顺式(1a)和反式(1b)
丁香酚。这样做,通过使用具有Pd催化作用的排队交叉偶联反应,已将1a的9步合成(先前报道)大大缩短为一个操作,从而消除了对任何保护基
化学反应的需要。