Iridium-Catalyzed Selective <i>trans</i>-Semihydrogenation of 1,3-Enynes with Ethanol: Access to (<i>E,E</i>)-1,4-Diarylbutadienes
Fengjie Huang, Zhidao Huang, Zhidao Huang, Guixia Liu, Zheng Huang, Zheng Huang
Abstract
A trans-semihydrogenation of 1,3-enynes with ethanol as the hydrogen source was developed using a new (PCN)Ir complex as the precatalyst and tBuNH2 as the cocatalyst. This catalyst system provides an efficient and atom-economical access to unsymmetrical (E,E)-1,4-diarylbutadienes with high yields and stereoselectivities. Monitoring the process revealed that a sequence of cis-semihydrogenation of the triple bond of 1,3-enynes (to form (E,Z)-butadienes) and (E,Z)-to-(E,E) isomerization occurs to form (E,E)-butadienes.
Topics & Concepts
ChemistryIsomerizationCatalysisIridiumEthanolCombinatorial chemistryMedicinal chemistrySequence (biology)Atom (system on chip)StereochemistryOrganic chemistryComputer scienceBiochemistryParallel computingAsymmetric Hydrogenation and CatalysisCarbon dioxide utilization in catalysisSynthetic Organic Chemistry Methods