Isolation and structural characterization of stable carbamic-carbonic anhydrides: an experimental and computational study

Carbamic-carbonic anhydrides are elusive species that have been only indirectly detected under controlled conditions. This functional group is transiently formed during the reaction of secondary amines with anhydrides in the presence of nucleophilic catalysts such as 4-(dimethylamino)pyridine. In th...

Full description

Saved in:
Bibliographic Details
Published inORGANIC CHEMISTRY FRONTIERS Vol. 9; no. 8; pp. 2154 - 2163
Main Authors Sampaio-Dias, Ivo E., Sousa, Carlos A. D., Silva-Reis, Sara C., da Silva, Luis Pinto, Garcia-Mera, Xerardo, Rodriguez-Borges, Jose E.
Format Journal Article
LanguageEnglish
Published CAMBRIDGE Royal Soc Chemistry 12.04.2022
Royal Society of Chemistry
Subjects
Amines
Anhydrides
Catalysts
Chemistry
Chemistry, Organic
Computer applications
Controlled conditions
Decarboxylation
Functional groups
NMR
Nuclear magnetic resonance
Orbital stability
Organic chemistry
Physical Sciences
Science & Technology
Structural analysis
Thermal analysis
INHIBITORS
MODEL
AMINES
DERIVATIVES
Online AccessGet full text

Cover

More Information
Summary:Carbamic-carbonic anhydrides are elusive species that have been only indirectly detected under controlled conditions. This functional group is transiently formed during the reaction of secondary amines with anhydrides in the presence of nucleophilic catalysts such as 4-(dimethylamino)pyridine. In this work, the synthesis and isolation of two carbamic-carbonic anhydrides are reported, including the first-ever solid-state structure of this functional group. The remarkable stability of these chiral carbamic-carbonic anhydrides allowed their study by NMR, HRMS, FTIR-ATR, and thermal analysis techniques (DSC and TGA). A thorough analysis of the bonding situation by computational studies hints that the origin of this unusual stability relies on n -> sigma* stabilizing orbital interactions hampering the occurrence of decarboxylation.
Bibliography:FCT
ISSN:2052-4129
2052-4110
2052-4110
DOI:10.1039/d2qo00038e