Herein, we present (E)-selective transfer semihydrogenation of alkynes based on an iridium complex in situ generated from [Ir(COD)Cl]₂ and an unsymmetrical (bearing two different phosphorous centers), ferrocene-based phosphine ligand utilizing formic acid as a hydrogen donor. Interestingly, a ligand-to-metal ratio may be used to control the stereoselectivity of the semihydrogenation process: a ratio of 1:1 iridium to ligand led to the formation of (Z)-alkene as a major product, whereas a ratio of 1:2 gave exclusively (E)-alkene. The latter 1:2 catalytic system is distinguished by its unprecedented chemoselectivity and exceptional stereoselectivity, which is substantiated by the broad scope of tested substrates, including natural product derivatives. The intriguing difference in catalytic activity between unsymmetrical and symmetrical ferrocene-based ligands was attributed to divergent coordination and steric hindrance. The presented methodology constitutes a solution to the common limitations of the known catalytic systems for semihydrogenation.

在此，我们提出了基于由 [Ir(COD)Cl] ₂和不对称（具有两个不同的磷中心）、二茂铁基膦配体利用甲酸作为原位产生的铱络合物的( E )-选择性转移半氢化炔烃。氢供体。有趣的是，配体与金属的比例可用于控制半氢化过程的立体选择性：1:1 的铱与配体的比例导致形成 ( Z )-烯烃作为主要产物，而比例为 1 :2 专门给 ( E)-烯烃。后一种 1:2 催化体系以其前所未有的化学选择性和出色的立体选择性而著称，这一点得到广泛的测试底物范围的证实，包括天然产物衍生物。不对称和对称二茂铁基配体之间催化活性的有趣差异归因于不同的配位和空间位阻。所提出的方法构成了对已知半氢化催化系统的共同限制的解决方案。