Manganese-catalyzed dehydrogenative synthesis of urea derivatives and polyureas
Abstract
Urea derivatives have significant applications in the synthesis of resin precursors, dyes, agrochemicals, and pharmaceutical drugs. Furthermore, polyureas are useful plastics with applications in coating, adhesive, and biomedical industries. However, the conventional methods for the synthesis of urea derivatives and polyureas involve toxic reagents such as (di)isocyanates, phosgene, CO, and azides. We present here the synthesis of (poly)ureas using much less toxic reagents─(di)amines and methanol─via a catalytic dehydrogenative coupling process. The reaction is catalyzed by a pincer complex of an earth-abundant metal, manganese, and liberates H2 gas, valuable by itself, as the only byproduct, making the overall process highly atom-economic. A broad variety of symmetrical and unsymmetrical urea derivatives and polyureas have been synthesized in moderate to quantitative yields using this catalytic protocol. Mechanistic insights have also been provided using experiments and DFT computation, suggesting that the reaction proceeds via an isocyanate intermediate.
Citation
Owen , A , Preiss , A , Mcluskie , A , Gao , C , Peters , G , Buehl , M & Kumar , A 2022 , ' Manganese-catalyzed dehydrogenative synthesis of urea derivatives and polyureas ' , ACS Catalysis , vol. 12 , pp. 6923-6933 . https://doi.org/10.1021/acscatal.2c00850
Publication
ACS Catalysis
Status
Peer reviewed
ISSN
2155-5435Type
Journal article
Description
A.K. thanks the Leverhulme Trust for an early career fellowship (ECF-2019-161). M.B. wishes to thank the School of Chemistry and EaStCHEM for their support. A.E.O. gratefully acknowledges a fellowship from the Akwa Ibom State University (TETFund).Collections
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