biostudies-literatureBaek YCamille and Henry Dreyfus FoundationHarvard UniversityKwanjeong Educational FoundationNational Institute of General Medical SciencesNIGMS NIH HHS16944-16953https://www.ebi.ac.uk/biostudies/studies/S-EPMC7262787biostudies-literatureUnknown141(42)We report the catalytic C-H amination mediated by an isolable CoIII imido complex (TrL)Co(NR) supported by a sterically demanding dipyrromethene ligand (TrL = 5-mesityl-1,9-(trityl)dipyrrin). Metalation of (TrL)Li with CoCl2 in THF afforded a high-spin (S = 3/2) three-coordinate complex (TrL)CoCl. Chemical reduction of (TrL)CoCl with potassium graphite yielded the high-spin (S = 1) CoI synthon (TrL)Co which is stabilized through an intramolecular η6-arene interaction. Treatment of (TrL)Co with a stoichiometric amount of 1-azidoadamantane (AdN3) furnished a three-coordinate, diamagnetic CoIII imide (TrL)Co(NAd) as confirmed by single-crystal X-ray diffraction, revealing a rare trigonal pyramidal geometry with an acute Co-Nimido-C angle 145.0(3)°. Exposure of 1-10 mol % of (TrL)Co to linear Journal of the American Chemical SocietyDirect Manipulation of Metal Imido Geometry: Key Principles to Enhance C-H Amination Efficacy.PMC7262787GM-115815R01 GM115815Baek YHennessy ETBetley TAfalseDirect Manipulation of Metal Imido Geometry: Key Principles to Enhance C-H Amination Efficacy.We report the catalytic C-H amination mediated by an isolable CoIII imido complex (TrL)Co(NR) supported by a sterically demanding dipyrromethene ligand (TrL = 5-mesityl-1,9-(trityl)dipyrrin). Metalation of (TrL)Li with CoCl2 in THF afforded a high-spin (S = 3/2) three-coordinate complex (TrL)CoCl. Chemical reduction of (TrL)CoCl with potassium graphite yielded the high-spin (S = 1) CoI synthon (TrL)Co which is stabilized through an intramolecular η6-arene interaction. Treatment of (TrL)Co with a stoichiometric amount of 1-azidoadamantane (AdN3) furnished a three-coordinate, diamagnetic CoIII imide (TrL)Co(NAd) as confirmed by single-crystal X-ray diffraction, revealing a rare trigonal pyramidal geometry with an acute Co-Nimido-C angle 145.0(3)°. Exposure of 1-10 mol % of (TrL)Co to linear 2019-01-01T00:00:00Z2019 Oct2025-05-18T12:08:16.266Z2020-06-05T07:07:21ZS-EPMC72627873155016210.1021/jacs.9b09015