Novel Fluorinated Biphenyl Compounds Synthesized via Pd(0)-Catalyzed Reactions: Experimental and Computational Studies

Five new difluorinated biphenyl compounds, 4 & PRIME;-(tert-butyl)-3,4-difluoro-1,1 & PRIME;-biphenyl (TBDFBP), 1-(3 & PRIME;,4 & PRIME;-difluoro-[1,1 & PRIME;-biphenyl]-4-yl)ethanone (DFBPE), 3 & PRIME;,4 & PRIME;-difluoro-2,5-dimethoxy-1,1 & PRIME;-biphenyl (DFDMBP), 3,4-difluoro-3 & PRIME;-nitro-1,1 & PRIME;-biphenyl (DFNBP), and (3 & PRIME;,4 & PRIME;-difluoro-[1,1 & PRIME;-biphenyl]-3-yl)(methyl)sulfane (DFBPMS), have been successfully synthesized by the well-knownSuzuki-Miyaura coupling with excellent yields averaging 78%.UV-visible, Fourier transform infrared ,and (CNMR)-C-13 and H-1 NMR spectroscopies along with single-crystalX-ray diffraction (SC-XRD) analysis (for TBDFBP and DFBPE) were used for the structure elucidation of the synthesized compounds.The SC-XRD results demonstrated the crystal systems of the studiedcompounds, TBDFBP and DFBPE, to be monoclinic,and their space groups were found to be P2(1)/c. Also, a detailed density functional theory studywas performed. The calculated structures for TBDFBP and DFBPE were found to agree quite well with the experimental results. Thenatural bonding orbital charge analysis suggested that molecules ofthese compounds should interact quite noticeably with each other inthe solid phase and with polar solvent molecules. Molecular electrostaticpotential analysis suggests that accumulation of positive and negativepotential implies possibility of quite significant dipole-dipoleintermolecular interactions in crystals of these compounds, as wellas quite strong interactions with polar solvent molecules. The globalreactivity parameters analysis suggests all compounds to be quitestable in redox reactions, with the compound DFNBP beingrelatively more reactive and the compounds TBDFBP and DFDMBP being relatively more stable.