Borylene as an electron-pair donor for P … B pnicogen bonds

摘要: Ab initio MP2/aug’-cc-pVTZ calculations have been performed on the complexes (CO)2(HB):PXH2 and (N2)2(HB):PXH2, for X = F, Cl, NC, OH, CN, CCH, CH3, H, in order to investigate properties of these which are stabilized by P … B pnicogen bonds, with electron-pair donor. The binding energies exhibit an exponential dependence P-B distance, but they do not correlate MEP minima (CO)2(HB) (N2)2(HB), nor maxima PXH2. For fixed X, energy (N2)2(HB):PXH2 is greater than that (CO)2(HB):PXH2. Charge-transfer stabilizes both series complexes, occurs from electron pair antibonding P-A σ orbital, A atom X directly bonded P. These charge-transfer also distance. In (CO)2(HB):PXH2, there a second interaction lone P π orbitals two C-O groups. Electron density analyses indicate bonds relatively weak interactions little covalent character. chemical shieldings 11B essentially unaffected complex formation. contrast, 31P increase 10 50 ppm four most strongly bound decrease −4 −12 ppm remaining complexes. each EOM-CCSD spin-spin coupling constants 1pJ(P-B) quadratically decreasing compared (N2)2(HB):PXH2.