8-methylidene-1,4-dioxaspiro[4.5]decane

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 250 mL round-bottom flask equipped with a reflux condenser was charged with zinc-copper couple (6.5 g, 0.05 mol) and ethyl ether (100 mL). Iodine (0.42 g, 0.00165 mol) was added and stirred until the brown color disappeared. Diiodomethane (26.56 g, 0.09915 mol) was added and heated at reflux for 2 h. 8-Methylene-1,4-dioxaspiro[4.5]decane (10 g, 0.06 mol), dissolved in ethyl ether (50 ml) was added and the mixture was heated at roflux overnight. An additional portion of diiodomethane (26.56 g, 0.09915 mol), zinc-copper couple (6.5 g, 0.05 mol) and iodine (0.42 g, 0.00165 mol) was added and the reaction was continued at reflux for overnight. The reaction mixture was cooled to room temperature, filtered, and the precipitate was rinsed with ethyl ether (100 mL). The combined ether solutions were placed in a 500 mL round-bottom flask and IN hydrochloric acid (200 mL) was added and stirred at room temperature for 1 hour. The layers were separated and the aqueous layer was extracted with ethyl ether (2×200 mL). The combined organic layers were dried and concentrated under educed pressure. The residue was purified by flash chromatography to afford the desired product. (4.6 g 50%). A 250 mL round-bottom flask equipped with a reflux condenser heated at reflux for 2 h was added the mixture was heated at roflux overnight at reflux for overnight filtered the precipitate was rinsed with ethyl ether (100 mL) The combined ether solutions were placed in a 500 mL round-bottom flask and IN hydrochloric acid (200 mL) was added stirred at room temperature for 1 hour The layers were separated the aqueous layer was extracted with ethyl ether (2×200 mL) The combined organic layers were dried concentrated under educed pressure The residue was purified by flash chromatography

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 1,4-Dioxaspiro[4.5]decan-8-one (21 g, 0.13 mol) in dry benzene (50 mL, 0.6 mol) was added to ethylenetriphenylphosphorane [prepared from dimsyl sodium and methyltriphenylphosphonium bromide (106 g, 0.291 mol) in dimethyl sulfoxide (600 mL, 8 mol)] The mixture was stirred at room temperature overnight and poured into a separating funnel containing ethyl ether (500 mL) and water (500 mL). The organic layer was separated and the aqueous phase was extracted with ethyl ether (2×500 mL). The combined ether layers were washed with water (500 mL) and brine (500 mL), and dried. The solvents were removed under reduced pressure and the residue was purified by flash chromatography to afford the desired product (18.0 g, 85%). poured into a separating funnel The organic layer was separated the aqueous phase was extracted with ethyl ether (2×500 mL) The combined ether layers were washed with water (500 mL) and brine (500 mL) dried The solvents were removed under reduced pressure the residue was purified by flash chromatography

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir: