Addition of a B-H Bond across an Amido-Cobalt Bond: Co-II-H-Catalyzed Hydroboration of Olefins

作者：Pang, Maofu; Wu, Chengjuan; Zhuang, Xuewen; Zhang, Fanjun; Su, Mincong; Tong, Qingxiao^*; Tung, Chen-Ho; Wang, Wenguang^*

来源：Organometallics, 2018, 37(9): 1462-1467.

DOI：10.1021/acs.organomet.8b00114

• METAL-LIGAND COOPERATION
• ALKENE ISOMERIZATION-HYDROBORATION
• ENANTIOSELECTIVE HYDROBORATION
• ASYMMETRIC HYDROBORATION
• TERMINAL SELECTIVITY
• HYDRIDE COMPLEXES
• PINCER COMPLEXES
• IRON CATALYST
• HYDROGENATION
• REACTIVITY

This paper describes a well-defined cobalt(II) half-sandwich complex bearing a phosphinoaminato ligand, Cp*Co(1,2-Ph2PC6H4NH) (1), that can activate pinacolborane (HBpin) for catalytic terminal hydroboration of olefins. The cooperative cobalt(II)-amido reactivity in 1 enables the B-H bond cleavage, affording the 17-electron cobalt(II) hydride Cp*Co(1,2-Ph2PC6H4NH (Bpin)), abbreviated H1(Bpin), in which the borenium ion is captured by the uncoordinated nitrogen atom of the phosphinoaminato ligand. Hydroboration of the C=C bond can be promoted by a heteroatom such as N or O at the beta-position of terminal alkenes. The mechanism of such hydroboration was established by various stoichiometric reactions based on the cobalt(II) hydride. With cooperative Co-II-N reactivity for the B-H bond cleavage, our catalysis depends on the Co-II-H hydride generated by the system itself.

• 出版日期2018-5-14
• 单位山东大学; 汕头大学