TY - JOUR AU - Das, Dipendu; Khan, Hina P. A.; Chakraborty, Tushar Kanti TI - Ti(III)-Mediated Radical-Induced Approach to a Bicyclic δ-Lactone with a Bridgehead β-Hydroxy Group SN - 0039-7881 SN - 1437-210X PY - 2018 JO - Synthesis JF - Synthesis LA - EN VL - 50 IS - 15 SP - 3006 EP - 3014 ET - 2018/07/05 DA - 2018/07/19 KW - quaternary center KW - bridgehead hydroxy KW - Cp2TiCl KW - bicyclic lactone KW - radical cyclization KW - Tamao–Fleming oxidation AB - Herein, we portray a synthetic route to a bicyclic lactone containing a bridgehead hydroxy group, a structure that is present in many natural products of biological and medicinal relevance. Ethyl (E)-3-(dimethylphenylsilyl)-7,8-epoxyoct-2-enoate underwent radical-mediated­ reductive epoxide opening with concomitant intramolecular cyclization using Cp2Ti(III)Cl to give cis-6-(dimethylphenylsilyl)-3-oxabicyclo[4.3.0]nonan-4-one, a bicyclic lactone with a bridgehead silyl group serving as a masked hydroxy group. Furthermore, the bridgehead C–Si bond underwent stereoretentive oxidative cleavage to give cis-6-hydroxy-3-oxabicyclo[4.3.0]nonan-4-one in high yield under Tamao–Fleming oxidation conditions; this demonstrates the potential utility of this strategy in the synthesis of many natural products bearing similar hydroxylated bridgehead chiral center embedded in a bicyclic lactone framework. PB - © Georg Thieme Verlag DO - 10.1055/s-0037-1609586 UR - http://www.thieme-connect.de/products/ejournals/abstract/10.1055/s-0037-1609586 ER -