A PROOF OF DIELS-ALDER EXO ISOMER MECHANISTIC SURPRISE
نویسندگان
چکیده
Critical analysis of published works shows that there is no evidence any Diel- Alder reactions took place in a synchronous manner. The Diel-Alder 4+2 cyclo addition conjugated dienes and dinophiles which represents some mechanistic surprises endo exo products/isomers. Kinetically, product more preffered to isomer because its low activation energy. Therefore this experiment carried out support exo-configuration product. preparation exo-cis-3,6- endoxotetrahydrophthalic anhydride (16.9g, 44.86%) with melting point 116.80c – 120.50c IR 1781,1857 recorded on perkin elmer spectrum, Bx-FT system using KBr disk 1Hr NMR(500MHz CDC13) the Reichert Thermovar hot stage apparatus by reaction furan(25g, 0.368mol) maleic (22g, 0.224 mol) diethylether. Preparation bromolactonic acid pseudo ester were also discussed. It was found as literature their exo-adduct 1140c for 116.80c. Also, NMR spectrum signal most proton absorption proof. functional groups behave expected. then concluded exo- isomer/product thermodynamically stable exo-product indicated still remains significant major
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ژورنال
عنوان ژورنال: Bulletin of the Chemical Society of Nigeria
سال: 2022
ISSN: ['0795-2066']
DOI: https://doi.org/10.46602/jcsn.v47i4.796