Cyclohexane → 1-Pentadecene-5-phosphonic acid diethyl ester

Temperature

0 °C

A solution of 4-pentenyl phosphonic acid diethyl ester (2.832 g, 13.7 mmol) in anhydrous tetrahydrofuran (20 mL) and cooled to about −78° C. A 1.3 M solution of sec-butyl lithium in cyclohexane (15 mL, 19.5 mmol) was added slowly to the mixture keeping the temperature below −60° C. 1-Iododecane (6.32 g, 23.6 mmol, 1.8 eq.) was then added slowly to the reaction mixture. The mixture was warmed to 0° C. and was stirred for three hours. The reaction was then quenched with NH4Cl (saturated, 20 mL). The mixture was warmed to room temperature and the THF was removed by rotary evaporation. The resulting solution was extracted with ethyl acetate (50 mL). The organic layer was separated and dried over Na2CO3. The solvent was removed and the resulting residue was purified by column chromatography (silica, ethyl acetate/hexane=2/8 then 4/6) to provide the pure product (3.46 g, 73% yield). 1H NMR (CDCl3) δ=5.8 (m, 1H), 5.0 (m, 2H), 4.1 (m, 4H), 2.2 (m, 2H), 1.8-1.2 (m, 27H), 0.9 (t, 3 H). 31P NMR (CDCl3) δ=35.8.

1. customthe temperature below −60° C
2. customThe reaction was then quenched with NH4Cl (saturated, 20 mL)
3. temperatureThe mixture was warmed to room temperature
4. customthe THF was removed by rotary evaporation
5. extractionThe resulting solution was extracted with ethyl acetate (50 mL)
6. customThe organic layer was separated
7. dry with materialdried over Na2CO3
8. customThe solvent was removed
9. customthe resulting residue was purified by column chromatography (silica, ethyl acetate/hexane=2/8

ORD record

ord-5fef42b7870649578ef030edbc0ec62c

Source dataset

uspto-grants-2010_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07754200B2