Whitby group

 General procedure E (see below) with diene 166 (4,4-bis(methoxymethyl)hepta-1,6-diene) (92.0 mg, 0.50 mmol), benzyl chloride (0.06 mL, 0.50 mmol) and trimethylsilyl cyanide (0.06 mL, 0.50 mmol).  Purification by column chromatography (SiO₂, hexane/Et₂O 3:1) gave the title compound as the major product (minor product: 195), a pale yellow oil (48.0 mg, 32%).

General procedure E: zirconocene mediated synthesis of cyclohexanones:

n-BuLi (2 eq.) was added dropwise to a solution of Cp2ZrCl2 (1 eq.) in dry THF (5.0 mL per 1.0 mmol of Cp2ZrCl2) at −78 °C. A solution of diene 166 (4,4-bis(methoxymethyl)hepta-1,6-diene) (1 eq.) in dry THF (3.0 mL per 1.0 mmol of diene 166) was added dropwise at −78 °C. The reaction mixture was warmed to room temperature and stirred for 2 h. The reaction mixture was cooled to −78 °C and the appropriate carbenoid precursor (1–1.3 eq.) and LDA (1–1.3 eq.) added sequentially. After stirring at −78 °C for 1 h the reaction mixture was warmed to −40 °C and the appropriate isonitrile (1–1.3 eq.) added. The reaction mixture was allowed to warm slowly to room temperature and stirred at this temperature for 16 h. 50% aq. HOAc solution (3 mL) was added to the reaction mixture followed by stirring at room temperature for 1 h. The reaction mixture was saturated with K2CO3, poured into water (100 mL) and extracted with ether (3 × 50 mL). The organic extracts were combined, washed sequentially with sat. aq. NaHCO3 (100 mL) and brine (100 mL), dried (MgSO4), filtered and the solvent removed in vacuo to give the crude product, which was purified as described