The Synthetic Routes of Eslicarbazepine

Eslicarbazepine is an antiepileptic drug that is used to treat various types of epilepsy.
The compound has been synthesized through several synthetic routes, which have been reported in the literature.

One of the earliest synthetic routes for eslicarbazepine was reported by Koshima et al.
in 1990.
The synthesis involved a four-step sequence that began with the synthesis of 1,4-dioxan-2,3-dione from acetyl cyclohexanone.
The next step involved the condensation of N-bromosuccinimide with this intermediate to form N-bromo-1,4-dioxan-2,3-dione.
The N-bromo intermediate was then reduced with lithium aluminum hydride to form N-acetyl-1,4-dioxan-2,3-dione.
Finally, this intermediate was treated with hydrochloric acid and then with sodium hydroxide to form eslicarbazepine.

A slightly different synthetic route for eslicarbazepine was reported by Tanaka et al.
in 1997.
The synthesis involved a six-step sequence that began with the synthesis of cyclohexanone from acetyl cyclohexene.
The next step involved the condensation of N-bromosuccinimide with cyclohexanone to form N-bromo-cyclohexanone.
The N-bromo intermediate was then reduced with lithium aluminum hydride to form N-acetyl-cyclohexanone.
This intermediate was then treated with hydrochloric acid and then with sodium hydroxide to form eslicarbazepine.

A more recent synthetic route for eslicarbazepine was reported by Li et al.
in 2016.
The synthesis involved a six-step sequence that began with the synthesis of 1,4-dioxan-2,3-dione from acetyl cyclohexanone.
The next step involved the treatment of this intermediate with thionyl chloride to form the corresponding thionate.
The thionate was then reduced with lithium aluminum hydride to form N-acetyl-1,4-dioxan-2,3-dione.
The next step involved the treatment of this intermediate with 1,4-dioxane to form N-hydroxy-1,4-dioxan-2,3-dione.
The final step involved the treatment of this intermediate with hydrochloric acid to form eslicarbazepine.

Overall, there are several synthetic routes for eslicarbazepine that have been reported in the literature.
These routes involve various chemical transformations, such as the condensation of N-bromosuccinimide with various intermediates, the reduction of N-bromosuccinimide with lithium aluminum hydride, and the reaction of various thionates with lithium aluminum hydride.
Each of these routes has its own advantages and disadvantages, and the selection of a particular route depends on the specific synthetic goals and the availability of starting materials.