Solvent-Dependent Divergent Functions of Sc(OTf)3 in Stereoselective Epoxide-Opening Spiroketalizations
نویسندگان
چکیده
A. Supplementary Figures S1–S2 S2 B. Complete data on spirocyclization of exo-glycal epoxide 6a S3 C. Materials and methods S4 D. Synthesis of propargyl alcohols 2a–h S5 E. Synthesis of exo-glycals 3a–h S8 F. Synthesis of TIPS-protected exo-glycals 4a–h S11 G. Synthesis of 4-substituted exo-glycals 4i–n S14 H. Synthesis of exo-glycal alcohols 5a–n S18 I. Synthesis of exo-glycal epoxides 6a–n S23 J. Sc(OTf) 3-mediated spirocyclization of exo-glycal epoxides 6 in THF with inversion of configuration (7a–n) S28 K. Sc(OTf) 3-mediated spirocyclization of exo-glycal epoxides 6 in CH 2 Cl 2 with retention of configuration (8a–n) S34 L. X-ray diffraction data for spiroketal 8b S41 M.
منابع مشابه
Solvent-dependent divergent functions of Sc(OTf)₃ in stereoselective epoxide-opening spiroketalizations.
A stereocontrolled synthesis of benzannulated spiroketals has been developed using solvent-dependent Sc(OTf)3-mediated spirocyclizations of exo-glycal epoxides having alcohol side chains. In THF, the reaction proceeds via Lewis acid catalysis under kinetic control with inversion of configuration at the anomeric carbon. In contrast, in CH2Cl2, Brønsted acid catalysis under thermodynamic control ...
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