Affiliation:
1. Department of Chemistry and Research Center for Chemical Biology and Omics Analysis College of Science Southern University of Science and Technology Shenzhen 518055 China
2. Department of Chemistry and Dongguan Key Laboratory for Data Science and Intelligent Medicine Great Bay University Dongguan 523000 China
3. Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications College of Chemistry and Materials Science Jinan University Guangzhou 510632 China
4. State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 China
Abstract
AbstractFeaturing an extra electron in the π* antibonding orbital, species with a 2‐center‐3‐electron (2c3e) π bond without an underlying σ bond are scarcely known. Herein, we report the synthesis, isolation and characterization of a radical anion salt [K(18‐C‐6)]+{[(HCNDipp)2Si]2P2}⋅− (i.e. [K(18‐C‐6)]+3⋅−) (18‐C‐6=18‐crown‐6, Dipp=2,6‐diisopropylphenyl), in which 3⋅− features a perfectly planar Si2P2 four‐membered ring. This species represents the first example of a Si‐ and P‐containing analog of a bicyclo[1.1.0]butane radical anion. The unusual bonding motif of 3⋅− was thoroughly investigated via X‐ray diffraction crystallography, electron paramagnetic resonance spectroscopy (EPR), and calculations by density functional theory (DFT), which collectively unveiled the existence of a 2c3e π bond between the bridgehead P atoms and no clearly defined supporting P−P σ bond.
Funder
National Natural Science Foundation of China
Shenzhen Science and Technology Innovation Program
Guangdong Provincial Key Laboratory of Environmental Catalysis and Health Risk Control, Guangdong University of Technology