# Study of the interaction of 2H-furo[3,2-b]pyran-2-ones with nitrogen-containing nucleophiles

## TL;DR

This study explores how certain chemical compounds react with nitrogen-based molecules, leading to new methods for synthesizing specific ring structures.

## Contribution

The paper introduces a new general method for synthesizing substituted pyrazol-3-ones containing the allomaltol fragment.

## Key findings

- Reactions with aliphatic amines produce 2H-furo[3,2-b]pyran-2,7(3H)-diones with exocyclic enamine groups.
- Dinucleophiles cause recyclization and furan ring opening, enabling synthesis of pyrazol-3-ones.
- X-ray diffraction confirmed the structures of all synthesized products.

## Abstract

For the first time, the reaction of substituted 2H-furo[3,2-b]pyran-2-ones with diverse N-nucleophiles was investigated. It was shown that the direction of the process depends on the type of employed nitrogen-containing reagent. For example, condensation with aliphatic amines leads to 2H-furo[3,2-b]pyran-2,7(3H)-diones bearing an exocyclic enamine moiety. At the same time, interaction with dinucleophiles results in recyclization accompanied by opening of the furan ring. Relied on the aforementioned process a general method for the synthesis of substituted pyrazol-3-ones with allomaltol fragment was designed. Structures of representatives of all obtained products were unambiguously confirmed by X-ray diffraction.