1H and 13C NMR data of benzylsulfonic acids-model compounds for lignosulfonate

Bjart F Lutnaes1, Bernt O Myrvold, Rolf A Lauten

  • 1Department of Chemistry, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway. bjart.frode.lutnaes@borregaard.com

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According to the molecular orbital (MO) model, benzene has a planar structure with a regular hexagon of six sp2 hybridized carbons. As shown in Figure 1, each carbon is bonded to three other atoms with C–C–C and H–C–C bond angles of 120°. The C–H bond length is 109 pm, and the C–C bond length is 139 pm which is midway between the single bond length of sp3 hybridized carbons (154 pm) and sp2 hybridized carbons (133 pm).
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In 1865, August Kekule suggested the structure of benzene according to the structural theory of organic chemistry based on the three assertions—formula of benzene is C6H6, all the hydrogens of benzene are equivalent, and each carbon must have four bonds due to its tetravalency.
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