Exploring the generation and use of acylketenes with continuous flow processes

The generation and use of reactive intermediates is well suited to continuous flow processing owing to the ability to scale up reactions, contain hazards and heat solvents past their atmospheric temperature boiling points. Herein we explore the chemistry of acylketenes, generated from commercially available 2,2,6-trimethyl-4H-1,3-dioxin-4-one (TMD, 10) under continuous flow conditions. The developed flow chemistry system is capable of permitting a wide range of applications of these acylketene intermediates, including access to equilibrating processes that result in ketone exchange. Some of the dioxinone products resulting from this study are destabilised towards acylketene generation, this is demonstrated through their ability to generate acylketene at lower reaction temperatures4915591564CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP4538622014-42014/26378-2; 2014/25770-6The authors gratefully acknowledge financial support from Cardiff University's allocation of the Higher Education Funding Council Wales GCRF QR Fund (D. L. B.). This project was also partly supported by seed funding from the São Paulo Research Foundation – FAPESP (J. C. P., awards No. 2014/26378-2 and 2014/25770-6), CNPq [(J. C. P., award No. 453862) (SWE No. 207161/2017-8; R. G.)] and CAPES (2014-4; R. G.