1591991-93-3Relevant articles and documents
Iron-Catalyzed Synthesis of Five-Membered Cyclic Carbonates from Vicinal Diols: Urea as Sustainable Carbonylation Agent
Pe?a-López, Miguel,Neumann, Helfried,Beller, Matthias
, p. 3721 - 3727 (2016)
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.
Cooperative catalysis of cyclic carbonate ring opening: Application towards non-isocyanate polyurethane materials
Lombardo, Vince M.,Dhulst, Elizabeth A.,Leitsch, Emily K.,Wilmot, Nathan,Heath, William H.,Gies, Anthony P.,Miller, Matthew D.,Torkelson, John M.,Scheidt, Karl A.
supporting information, p. 2791 - 2795 (2015/05/05)
The reaction between cyclic carbonates and amines to produce hydroxyurethanes is an important alternative to current urethane chemistry. In order to address the issue of slow reaction rates, an efficient ring opening of cyclic carbonates with amines has been achieved utilizing cooperative catalysis. A new Lewis acid/Lewis base combination substantially decreases the reaction times for small molecule systems to reach complete conversion. Although triazabicyclodecene (TBD) has a substantial impact on the reaction rate, the addition of lithium triflate (LiOTf) as a co-catalyst allows for the fastest ring opening reported in the current literature. Cooperative catalysis is also applied to the synthesis of polymers containing hydroxyurethane linkages and is able to achieve rapid conversion of the bis-cyclic carbonate and diamine precursors when compared with the uncatalyzed reaction.
