Carboxyl–Group Removal and Return: Mechanistic and Strategic Advances in Decarboxylation–Carboxylation
Year: 2026
Type: preprint
Abstract: Carboxylic acids are ubiquitous functionalities and indispensable synthetic linchpins in organic chemistry. In recent years, strategies involving the removal, exchange, or recycling of the carboxyl group, particularly decarboxylation and carboxylation have gained remarkable momentum, partly driven by the imperative to valorize carbon dioxide generated in chemical transformations. Beyond simple CO2 extrusion, tandem decarboxylation–carboxylation and related cyclic processes have emerged as powerful yet underexplored approaches for constructing carboxylic acids in a single operation. This review highlights recent advances (2000–2026) in decarboxylation–re-carboxylation chemistry, with an emphasis on mechanistic understanding, reactive intermediates, and the strategic use of CO2 as a transient functional handle. We introduce a unified conceptual framework that classifies carboxyl–group transfer based on the identity of the carbon shuttle, the timing and mode of carboxyl reintroduction, and the nature of reactive intermediates. Subsequent sections discuss three major mechanistic archetypes: CO2–cycling decarboxylation–re-carboxylation, ester–cycling decarboxylation–re-esterification, and non-in situ carboxyl transfer using exogenous CO2 or alternative carboxyl sources. By delineating key developments and conceptual trends, we aim to inspire further innovation in exploiting carboxyl–group recycling as a platform for sustainable molecular synthesis.
Source: ChemRxiv
Language: English
Subfield: Process Chemistry and Technology
Field: Chemical Engineering
Domain: Physical Sciences
SDG: Climate action
Open Access status: green
OpenAlex ID: W7220363644