one-component organocatalyst for the atom-economic transformation of epoxides to oxazolidinones under microwave irradiation. Integrating a positively charged center into phenols over a modular one-step preparation gives rise to a bifunctional system with improved acidity and activity, competent in rapid assembly of epoxides and isocyanates under microwave irradiation in a short reaction time (20–60 min)
Bimetallic Aluminum(salen) Catalyzed Synthesis of Oxazolidinones from Epoxides and Isocyanates
作者:Thilo Baronsky、Christopher Beattie、Ross W. Harrington、Reyhan Irfan、Michael North、Javier G. Osende、Carl Young
DOI:10.1021/cs4001046
日期:2013.4.5
aluminum(salen) complex [Al(salen)]2O is shown to catalyze the synthesis of oxazolidinonesfromepoxides and isocyanates. The reaction is demonstrated to proceed with overall retention of epoxide stereochemistry, and both aromatic and aliphatic isocyanates can be used as substrates. In contrast to the corresponding reactions between epoxides and carbon dioxide or carbon disulfide which are also catalyzed by [Al(salen)]2O
Synthesis of Oxazolidinones from Epoxides and Isocyanates Catalysed by Aluminium Heteroscorpionate Complexes
作者:José A. Castro-Osma、Amy Earlam、Agustín Lara-Sánchez、Antonio Otero、Michael North
DOI:10.1002/cctc.201600407
日期:2016.6.21
of an aluminium(heteroscorpionate) complex and tetrabutylammonium bromide acts as a highly efficient catalyst system for the synthesis of oxazolidinonesfromepoxides and isocyanates. Twenty two complexes were tested derived from a range of bispyrazole ligands and containing 1–3 aluminium atoms per complex. The optimal catalyst was found to be a bimetallic complex of a thioacetamidate ligand. Under
Isocyanurate Formation During Oxazolidinone Synthesis from Epoxides and Isocyanates Catalysed by a Chromium(Salphen) Complex
作者:Xiao Wu、Jess Mason、Michael North
DOI:10.1002/chem.201702948
日期:2017.9.18
A tale of two reactions: A chromimium(salphen) complex catalyses the formation of oxazolidinonesfromepoxides and isocyanates. However, with particularly electron-deficient isocyanates, the complex catalyses cyclotrimerisation of the isocyanate to an isocyanurate instead (see scheme).
Vanadium<sup>V</sup>(salen) catalysed synthesis of oxazolidinones from epoxides and isocyanates
作者:Christopher Beattie、Michael North
DOI:10.1039/c4ra04427d
日期:——
vanadiumV(salen) complex V+O(salen) EtOSO3− and tetrabutylammonium bromide forms a highly active catalyst system for the reaction between epoxides and isocyanates leading to oxazolidinones. The reaction conditions were optimized and the optimal conditions (80 °C in toluene for 5 hours with 2 mol% of vanadium catalyst and 2 mol% of tetrabutylammonium bromide cocatalyst) applied to eight epoxides and six aromatic