Tautomeric Equilibria in Solutions of 2-Phenacylbenzimidazoles

Table 4

MP2(6-311+G(d,p)) calculated relative energies [kJ⋅mol⁻¹] of different tautomers.

Compound	Tautomer	R =	Energy [kJ⋅mol^−1]
2a	K	p-OCH3	0.00
2a	O	p-OCH3	10.06
2a	E	p-OCH3	33.94
2d	K	H	0.00
2d	O	H	6.29
2d	E	H	30.17
2i	K	p-NO2	0.00
2i	O	p-NO2	2.10
2i	E	p-NO2	23.05

Absolute energy: -875.8329 Hartree.
Absolute energy: -761.5722 Hartree.
Absolute energy: -965.6772 Hartree.