(2-((3R,5R)-3,5-Bis((tert-butyldimethylsilyl)oxy)cyclohexylidene)ethyl)diphenylphosphine oxide → (4aR,5R,8aS)-1-{(E)-2-[(3R,5R)-3,5-Bis-(tert-butyl-dimethyl-silanyloxy)-cyclohexylidene]-ethylidene}-5-((R)-1,5-dimethyl-5-trimethylsilanyloxy-hex-3-ynyl)-4a-methyl-decahydro-naphthalene

関与物質

反応手順

590 mg (1.03 mmol) of carefully dried (3R,5R)-[2-[3,5-bis-(t-butyldimethylsilanyloxy)-cyclohexylidene]-ethyl]-diphenyl-phosphine oxide (Tetrahedron Lett. 32, 7663 (1991)) was dissolved in 5 ml of abs. THF and treated at -78° with 0.644 ml of nBuLi (1.6M, hexane). 15 Minutes later, 187 mg (5.15 mmol) of (4aR,5R,8aR)-5-((R)-1,5-dimethyl-5-trimethylsilanyloxy-hex-3-ynyl)-4a-methyl-octahydro-naphthalen-1-one, dissolved in 0.5 ml of abs. THF, was added to the deep red solution and kept for 0.5 h at -78° and for 0.5 h at 0°. The reaction mixture was then poured onto crushed ice/KH2PO4, extracted twice with ether, washed with water and brine, dried over sodium sulfate, and the solvents carefully removed i.V. Flash chromatography (SiO2, hexane/AcOEt=95/5) afforded in the less polar fractions 129 mg of the title compound as colorless oil and in the more polar ones 67 mg of recovered ketone.

情報源と証拠