Selective Synthesis of Cyclooctanoids by Radical Cyclization of Seven‐Membered Lactones: Neutron Diffraction Study of the Stereoselective Deuteration of a Chiral Organosamarium Intermediate
نویسندگان
چکیده
Seven-membered lactones undergo selective SmI2 -H2 O-promoted radical cyclization to form substituted cyclooctanols. The products arise from an exo-mode of cyclization rather than the usual endo-attack employed in the few radical syntheses of cyclooctanes. The process is terminated by the quenching of a chiral benzylic samarium. A labeling experiment and neutron diffraction study have been used for the first time to probe the configuration and highly diastereoselective deuteration of a chiral organosamarium intermediate.
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