Synthesis of (−)-elemoxide, a commercially important fragrance compound

• Published in: Tetrahedron letters Vol. 59; no. 37; pp. 3413 - 3415
• Main Authors: Rodrigues, Lima, Majik, Mahesh S., Tilve, Santosh G., Wahidulla, Solimabi
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 12.09.2018; Elsevier
• Subjects: Chemistry; Chemistry, Organic; Elemoxide; Iodine-silane catalyses; Natural product; Oxymercuration –demercuration; Physical Sciences; Regioselective reaction; Science & Technology; Elemoxide; Natural product; Regioselective reaction; Iodine-silane catalyses; Oxymercuration –demercuration; ALCOHOLS; SYSTEM; SUPERBASES; ANNULATION; lodine-silane catalyses; DEMERCURATION; Oxymercuration -demercuration
• ISSN: 0040-4039; 1873-3581
• DOI: 10.1016/j.tetlet.2018.08.003

[Display omitted] •An efficient four steps synthesis of a fragrant sesquiterpene oxide is reported.•Regioselective epoxidation with m-CPBA.•Regioselective epoxide ring opening with lithium aluminium hydride.•Regioselective intramolecular hydroxy attack on unactivated alkene using iodine.•Identified key intermediate which solves the problem of complex mixture formation. (−)-Elemoxide, a fragrant compound was synthesised using commercially available elemol in four steps with overall yield of 32%. The cyclic ether skeleton was constructed via intramolecular hydroalkoxylation using I2 and PhSiH3 catalytic system. Also, intramolecular oxymercuration-demercuration was employed as an alternate approach for cyclization. The various regioselective strategies involving epoxidation of alkene, reduction of epoxide and intramolecular cyclization were the highlights of the work. The key intermediate diol serves as a versatile intermediate for the synthesis of elemoxide and elemene.