Green synthesis of 1-phenyl-1-ortho-xylene ethane in IL and reaction mechanism. Issue 25 (7th March 2017)

• Record Type: Journal Article
• Authors: Sun, Xuejun; Zhou, Xinming; Cao, Bobo; Cao, Ziping; Fu, Hui
• Is Part Of: RSC advances. Volume 7:Issue 25(2017)
• Page Start: 14998
• Page End: 15004
• Publication Date: 2017-03-07
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c6ra28009a
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : In this study, 1-phenyl-1- ortho -xylene ethane (PXE) is synthesized in IL and the catalysts used were AlCl3 in 1-butyl-3-methylimidazolium bromide ([BMIM][Br]) or 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]). Abstract : 1-Phenyl-1- ortho -xylene ethane (PXE) in IL was synthesized, and the catalysts used were AlCl3 in 1-butyl-3-methylimidazolium bromide ([BMIM][Br]) or 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]), and H2 SO4 . When the concentrations of AlCl3 in IL, ortho -xylene and styrene were 0.35, 0.03 and 0.005 mol, respectively, it could be discovered that ([BMIM][Br]) was the best catalyst. When the mole fraction concentration of AlCl3 /[BMIM][Br] was more than 0.40%, the reaction was able to achieve 100% conversion. When the reaction time was longer than 60 minutes, the percentage conversion of ortho -xylene attained was 100%. The mechanisms of the reaction were investigated by the DFT method at the B3LYP/6-311++G(d, p) level. The potential energy surface (PES) profile indicated that the energy of transition state was 22.59 kcal mol −1 . This indicated that the activation energy of reaction was 28.24 kcal mol −1, which illustrated that the reaction occurred easily. Vibrational frequencies were observed in FT-IR spectra, the corresponding vibrational modes ν s (H4–C3Al–H5) and ν as (H4–C3Al–H5) indicated that an Al 3+ ion was combined with a C3 atom. In addition, the repeated use of the catalysts was studied; the ionic liquids could still catalyze the reaction and the percentage yield of PXE was larger than 91% after 6 runs.