# Reactivity umpolung of the cycloheptatriene core in hexa(methoxycarbonyl)cycloheptatriene

## TL;DR

This paper explores a new chemical strategy to modify a cycloheptatriene compound, revealing unexpected reactivity patterns and forming various complex derivatives.

## Contribution

The study extends the reactivity umpolung approach to a specific cycloheptatriene derivative, uncovering new synthetic pathways and selectivity mechanisms.

## Key findings

- Reactions primarily occur at the α-position relative to the hydrogen atom due to conformer stability or ester group influence.
- Cascade reactions produce diverse derivatives like norcaradienes, dihydroindazoles, and hydrazonocycloheptatriene.

## Abstract

A reactivity umpolung approach for the derivatization of cycloheptatrienes was extended to hexa(methoxycarbonyl)cycloheptatriene, which forms the corresponding anion reactive towards electrophiles. Despite the presence of four potential reactive sites, the reactions mainly involve the initial electrophilic attack onto the α-position relative to the hydrogen atom. The selectivity is either due to the high stability of the α-nucleophilic conformer or due to the promotion by the adjacent ester group. Cascade reactions upon the target connection, if installed, include the formation of norcaradienes, dihydroindazoles, a tetracyclodecene and a hydrazonocycloheptatriene derivative.