Boron Heterocycles: from Aromaticity to Electronic Materials.

Oxaborolide;Oxaborine;Diborapentacene;Electronic Materials;Heterocycle;Pi-Stacking;Chemistry;Science;Chemistry

Chen, JinhuiWolfe, John P. ;

University of Michigan

关键词: Oxaborolide;    Oxaborine;    Diborapentacene;    Electronic Materials;    Heterocycle;    Pi-Stacking;    Chemistry;    Science;    Chemistry;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/64638/chenjh_1.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

The unsaturated organoboron heterocycles 1,2-oxaborolides, 1,2-dihydro-1,2-oxaborines and 6,13-dihydro-6,13-diborapentacenes have been prepared for the first time and studied.2-Substituted-2,5-dihydro-1,2-oxaboroles were prepared by either a ring closing metathesis from (allyloxy)(N,N-diisopropylamino)vinylborane or a boron-tin exchange reaction of 2,2-dibutyl-2,5-dihydro-1,2-oxastannole with phenylboron dichloride. Treatment with base afforded the corresponding 1,2-oxaborolides. The 1H, 13C, 11B NMR spectral chemical shift values of 2-phenyl-1,2-oxaborolide are very similar to those of 1-methyl-2-phenyl-1,2-azaborolide which implies a similarity in their electronic structure. On treatment with [Cp*RuCl]4 or (CH3CN)3Mn(CO)3PF6, 2-phenyl-1,2-oxaborolide was converted to RuCp* or Mn(CO)3 complexes, respectively. Structural characterization of both complexes by single-crystal X-ray diffraction indicated that the metals are n5-bound to the ligand.1,2-Dihydro-2-phenyl-1,2-oxaborine was obtained from the reaction of potassium 2-phenyl-1,2-oxaborolide with methylene chloride and base. The product was converted to its phenyl-Cr(CO)3 complex, which was structurally characterized. The intra-ring bond lengths of the heterocycle suggest that it has aromatic character.Pentacene and its derivatives are promising compounds for uses as organic electronic materials. Three derivatives of the related 6,13-dihydro-6,13-diborapentacenes have been prepared and structurally characterized. The dibromo- and dimethyl- derivatives show a π-π stacking in the solid state. In principle, this type of packing is more favorable for intermolecular electronic interaction than the herringbone stacking shown by pentacene.