Abstract
A [3+2] cycloaddition of diethyl 1 2-oxiranephosphonate to aryl isocyanates catalyzed by lanthanide cations is described The reaction is highly regioselective and 5-substituted 2-oxazolidinone phosphonates are obtained with a regioselectivity greater than 95 5 with respect to the 4-substituted regioisomer and in up to 84% yield When 20 mol % of Pybox-Yb3+ is used as a catalyst enantiomerically enriched products are obtained in up to 75% ee depending on the reaction conditions and the nature of the isocyanate Low temperatures benefit asymmetric induction but have an adverse effect on the regioselectivity for para-substituted aryl isocyanates (C) 2010 Elsevier Ltd All rights reserved
Original language | Unknown |
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Pages (from-to) | 2746-2752 |
Journal | Tetrahedron-Asymmetry |
Volume | 21 |
Issue number | 21-22 |
DOIs | |
Publication status | Published - 1 Jan 2010 |