Intramolekulare Beweglichkeit eines Dibenzo-[b,f]-1,4-thiazepin-5-oxids. 13. Mitteilung über siebengliedrige Heterocyclen

The kinetics of the equilibrium in aqueous solution between the diasteromers of 2-Chloro-11-(4-methyl-1-piperazinyl-4-oxide)-dibenzo-b, f]-1,4-thiazepine-5-oxide (V) have been investigated. Both isomers differ in the position of the oxygen atom of the sulphoxide group. The sulphoxide group. The isomer with a pseudo-equatorial oxygen atom is 0.75 kcal/mol more stable than the isomer with the pseudo-axial oxygen atom. The calculated free energies of activation δG≠ are 24.6 kcal/mol and 23.9 kcal/mol.