A reactivity-selectivity study of the Friedel-Crafts acetylation of 3,3′-dimethylbiphenyl and the oxidation of the acetyl derivatives

Table 3 Total energies, Gibbs free energies (298 K), and structural properties for 3,3′-dimethylbiphenyl and the monoacetyl isomers, x-Ac

Substituent	Total energy E (a.u.)	G₂₉₈(a.u.)	G₂₉₈relative to 5-Ac (kJ mol⁻¹)	θ^a(degrees)	ϕ^b(degrees)
None	−541.963044	−541.768297	−	38.7	−
2-Ac	−694.601204	−694.371990	33.7	49.1	60.8
4-Ac	−694.610042	−694.380270	12.0	37.3	0.2
5-Ac	−694.612983	−694.384835	0	39.0	0.7
6-Ac	−694.604265	−694.376276	22.5	54.4	31.3

Results from DFT B3LYP 6-31 G(d,p) calculations. ^aDihedral angle between the two benzene rings taken as the average of the C2-C1-C1′-C6′ and C6-C1-C1′-C2′ dihedral angles. ^bDihedral angle between the carbonyl group and the benzene ring to which it is attached taken as the C_Ar-C_Ar-C = O dihedral angle.

ISSN: 2661-801X