181783-75-5Relevant articles and documents
Molar scale synthesis of enantiopure stilbene oxide
Chang, Han-Ting,Sharpless, K. Barry
, p. 6456 - 6457 (1996)
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Stereochemical divergence in the formation of organic carbonates derived from internal epoxides
Whiteoak, Christopher J.,Martin, Eddy,Escudero-Adan, Eduardo,Kleij, Arjan W.
, p. 2233 - 2239 (2013)
Catalysis of the challenging cycloaddition of carbon dioxide to internal epoxides has been studied using iron (III) amine triphenolate complexes and particular focus has been given to the stereochemical regulation of this process. When pure cis- or trans-2,3-epoxybutane is used as substrate, the stereochemistry of the product can be controlled yielding selectively cis- or trans-cyclic carbonates for both epoxidic substrates. This stereochemical divergence relates to two accessible catalytic pathways leading to either the cis or trans product via two distinct ring-closure steps. The involved mechanism and stereocontrol is a function of the catalyst/co-catalyst loading, and is further influenced by the medium, temperature and catalyst/co-catalyst structure. Other trans-internal epoxides could also be successfully converted into the pure trans-cyclic carbonate products without any loss of stereochemical information.
Chiral Macrocyclic Organocatalysts for Kinetic Resolution of Disubstituted Epoxides with Carbon Dioxide
Ema, Tadashi,Yokoyama, Maki,Watanabe, Sagiri,Sasaki, Sota,Ota, Hiromi,Takaishi, Kazuto
supporting information, p. 4070 - 4073 (2017/08/15)
Among chiral macrocycles 1 synthesized, 1m with the 3,5-bis(trifluoromethyl)phenylethynyl group was the best organocatalyst for the enantioselective synthesis of cyclic carbonates from disubstituted or monosubstituted epoxides and CO2. The X-ray crystal structure of 1m revealed a well-defined chiral cavity with multiple hydrogen-bonding sites that is suitable for the enantioselective activation of epoxides. A catalytic cycle proposed was supported by DFT calculations.
Iron-Catalyzed Synthesis of Five-Membered Cyclic Carbonates from Vicinal Diols: Urea as Sustainable Carbonylation Agent
Pe?a-López, Miguel,Neumann, Helfried,Beller, Matthias
supporting information, p. 3721 - 3727 (2016/08/16)
A new iron-catalyzed synthesis of cyclic carbonates from the corresponding vicinal diols and urea is described. This straightforward transformation allows for the preparation of a variety of five-membered carbonates by employing an inexpensive and environmentally benign iron salt as the catalyst. The use of readily available feedstocks such as urea and polyols makes this a sustainable process. As ammonia is formed as the only stoichiometric byproduct, this process can also be characterized by its high atom economy.