Reactivity of the Nickel(0)−CO2−Imine System: New Pathway to Vicinal Diamines
摘要:
Nickela-2-oxazolidinones, formed by oxidative coupling of imines and CO2 with Ni-0, react with LiCl under mild conditions (4 degrees C, 1 atm) to afford vicinal diamines in up to 89% yield. The reaction is the first organometallic example of reductive imine coupling requiring CO2. In this system, CO2 is participatory and is not incorporated in the reaction products. These results represent an important addition to our understanding of the reactivity of metallacycles derived from CO2 and unsaturated compounds.
We present herein an unprecedented diastereoconvergent synthesis of vicinal diamines from diols through an economical, redox-neutral process. Under cooperative ruthenium and Lewis acid catalysis, readily available anilines and 1,2-diols (as a mixture of diastereomers) couple to forge two C−N bonds in an efficient and diastereoselective fashion. By identifying an effective chiral iridium/phosphoric