학술논문
CO2 Adducts of Carbodicarbenes: Robust and Versatile Organocatalysts for Chemical Transformation of Carbon Dioxide into Heterocyclic Compounds.
Document Type
Article
Author
Source
Subject
*ORGANOCATALYSIS
*CHEMICAL amplification
*EPOXY compounds
*CARBON dioxide fixation
*RING formation (Chemistry)
*PHOSPHONIUM compounds
*
*
*
*
*
Language
ISSN
1867-3880
Abstract
Abstract: Four CO2 adducts of carbodicarbenes (CDCs) were first synthesized and structurally characterized by means of NMR spectroscopy, high‐resolution mass spectrometry, and FTIR spectroscopy. The introduction of 13C‐labelled CO2 confirmed the formation of the corresponding carboxylated species. Thermogravimetric analysis (TGA) provided detailed information on their thermal decarboxylation processes. The novel CDC–CO2 adducts were subsequently applied as robust and versatile organocatalysts for the carboxylative cyclization of CO2 with aziridines, epoxides, or propargylic alcohols, affording 2‐oxazolidinones and cyclic carbonates in good to excellent yields (51–99 %) and high functional group tolerance. TGA results together with control experiments indicate that the in situ formed free CDC by decarboxylation of the corresponding CDC–CO2 adducts plays the key role to activate the substrates by its strong Lewis basicity. [ABSTRACT FROM AUTHOR]