Zhang Xiaolei of Jiangnan University and Yan Hong research team of Nanjing University work together to realize the boron hydrogen bond functionalization of carboranemethylamine

Article author: Zhang Xiaolei recently, Dr Zhang Xiaolei, School of pharmacy, Jiangnan University, and Professor Yan Hong, School of chemistry and chemical engineering, Nanjing University, made research progress in the field of carborane functionalization, realizing the selective boron hydrogen bond functionalization of carborane methylamine for the first time (Figure 1) This achievement "PD (II) - catalyzed synthesis of bifunctional carboranes via cage B − h activation of 1-ch 2nh 2 - o-carboranes" was published online in the Journal of chemical science of the Royal Society (DOI: 10.1039 / c8sc01154k) Figure 1 Selective boron hydrogen bond diarylation of carboranemethylamine (source: Chemical Science) carborane is a kind of polyhedral cage like cluster containing carbon, hydrogen and boron atoms They have a series of special properties, such as good thermal and chemical stability, hydrophobicity and three-dimensional structure, which make the application of these compounds have been extended to materials, medicine, energy and other fields Carboborane methylamine, as a class of carboborane derivatives containing amino groups, has been widely used in drug synthesis However, due to the fragility and strong coordination of amino groups in carboranemethylamine, the traditional synthesis strategy is difficult to realize the derivation of boron end, which largely limits the structural diversity of this species and is not conducive to the subsequent biological activity screening Through careful analysis, the selective diarylation of boron hydrogen bond in carboranemethylamine was realized by using the location effect of transient guiding group and the catalysis of palladium metal By this method, a series of bifunctional carborane derivatives with aromatic and amino groups in molecular structure can be rapidly prepared (Fig 2) The reaction showed good functional group compatibility, easy operation, no additional steps to pre activate the substrate or remove the guiding group, and the amino group in the product could be further transformed The above research work was supported by the National Natural Science Foundation of China and the natural science foundation of Jiangsu Province Fig 2 Palladium metal catalyzed synthesis of bifunctional carborane derivatives containing aryl and amino groups (source: Chemical Science) Fig 3 Study on the reactivity of active carborane imine metal complexes (source: Chemical Science) The first author of this paper is Dr Zhang Xiaolei of Jiangnan University He and Professor Yan Hong of Nanjing University are the co correspondents of this paper The research direction of the author is organometallic chemistry and is devoted to "reactive and catalytic chemistry based on active species" At present, two kinds of new boron hydrogen bond functional substrates (carboranaldehyde and carborane methylamine) have been developed based on the reactivity and catalytic chemistry of "active carborane imine metal complexes" (Figure 3) and used in carborane functional reactions (see this paper and J am Chem SOC 2017, 139, 14511) The follow-up plan will focus on the research of diversity, asymmetry and potential application of the reaction system Introduction to the author: Dr Zhang Xiaolei, Professor Yan Hong, reference: X.Zhang, H Yan, "PD (II) - catalyzed synthesis of bifunctionalized carboranes via cage B − activation of 1-ch 2 NH 2 - o-carboranes", chem SCI 2018, DOI: 10.1039/c8sc01154k