Iron-Catalyzed Selective Hydroboration of CO<sub>2</sub> by Cooperative B–H Bond Activation
Hongjie Gao, Jiong Jia, Chen‐Ho Tung, Wenguang Wang
Abstract
We report a novel iron(II) complex supported by an anionic phosphanyl-iminopyridinate ligand, Cp*Fe(Cy 2 PN═C 5 H 4 N) ( 1 ), which shows remarkable catalytic activity in the selective hydroboration of CO 2 with HBpin, producing boryl formate with a turnover frequency (TOF) of ∼1176 h –1 at room temperature. This catalysis involves cooperative metal–ligand reactivity for H–B bond activation, affording a key Fe(II)–H intermediate, Cp*FeH(Cy 2 PN(Bpin)C 5 H 4 N) ( 2 ), that binds the Bpin moiety at the non-coordinated amino site. The very fast and selective formoxy production can be conveniently coupled to the N -formylation of amines, which delivers a variety of formamides. In addition, the reduction of boryl formate to the CH 3 OBpin stage was also achieved by 1 with HBpin under N 2 .