Deactivation mechanisms of iodo-iridium catalysts in chiral amine racemization
نویسندگان
چکیده
The homogenous, [IrCp∗I2]2, SCRAM catalyst (1) is active in the racemization of chiral amines. NMR, kinetic and structural mechanistic studies have determined cause deactivation to occur when ammonia or methylamine are liberated by hydrolysis aminolysis intermediate imine, which tightly coordinate iridium centre block turnover. Control moisture substrate concentration can suppress deactivation, whilst partial reactivation spent was identified using hydroiodic acid.
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ژورنال
عنوان ژورنال: Tetrahedron
سال: 2021
ISSN: ['0040-4020', '1464-5416']
DOI: https://doi.org/10.1016/j.tet.2020.131823