期刊
CHEMICAL SCIENCE
卷 13, 期 43, 页码 12643-12650出版社
ROYAL SOC CHEMISTRY
DOI: 10.1039/d2sc04207j
关键词
-
资金
- DFG [SCHU 1069/27-1]
- University of Duisburg-Essen
- Max Planck Institute for Chemical Energy Conversion
This study reports the synthesis of two L(X)Ga-substituted diphosphenes and their reactivity, showing that carbene coordination can modulate their electronic structure and oxidation properties.
Modulating the electronic structures of main group element compounds is crucial to control their chemical reactivity. Herein we report on the synthesis, frontier orbital modulation, and one-electron oxidation of two L(X)Ga-substituted diphosphenes [L(X)GaP](2) (X = Cl 2a, Br 2b; L = HC[C(Me)N(Ar)](2), Ar = 2,6-i-Pr2C6H3). Photolysis of L(Cl)GaPCO 1 gave [L(Cl)GaP](2) 2a, which reacted with Me3SiBr with halide exchange to [L(Br)GaP](2) 2b. Reactions with (NHC)-N-Me ((NHC)-N-Me = 1,3,4,5-tetramethylimidazol-2-ylidene) gave the corresponding carbene-coordinated complexes L(X)GaPP((NHC)-N-Me)Ga(X)L (X = Cl 3a, Br 3b). DFT calculations revealed that the carbene coordination modulates the frontier orbitals (i.e. HOMO/LUMO) of diphosphenes 2a and 2b, thereby affecting the reactivity of 3a and 3b. In marked contrast to diphosphenes 2a and 2b, the cyclic voltammograms (CVs) of the carbene-coordinated complexes each show one reversible redox event at E-1/2 = -0.65 V (3a) and -0.36 V (3b), indicating their one-electron oxidation to the corresponding radical cations as was confirmed by reactions of 3a and 3b with the [FeCp2][B(C6F5)(4)], yielding the radical cations [L(X)GaPP((NHC)-N-Me)Ga(X)L]B(C6F5)(4) (X = Cl 4a, Br 4b). The unpaired spin in 4a (79%) and 4b (80%) is mainly located at the carbene-uncoordinated phosphorus atoms as was revealed by DFT calculations and furthermore experimentally proven in reactions with (Bu3SnH)-Bu-n, yielding the diphosphane cations [L(X)GaPHP((NHC)-N-Me)Ga(X)L]B(C6F5)(4) (X = Cl 5a, Br 5b). Compounds 2-5 were fully characterized by NMR and IR spectroscopy as well as by single crystal X-ray diffraction (sc-XRD), and compounds 4a and 4b were further studied by EPR spectroscopy, while their bonding nature was investigated by DFT calculations.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据