Diethyl Ether → Ethyl 3-methyltridec-2E-enoate

Temperature

-78 °C

Decyl magnesium bromide (2.4 mL of a 2.0 M soln in ether, 4.8 mmol) CuCN (221 mg, 2.49 mmol) were suspended in anhydrous ether and cooled to −78° C. The mixture was warmed to 0° C. for 5 minutes and cooled to −78° C. The triflate D (220 mg, 0.83 mmol) was dissolved in anhydrous ether and added to the decyl magnesium and CuCN solution dropwise. The mixture was stirred vigorously for 2.5 hours. The solution was then warmed to 0° C. and quenched with a 10% aqueous ammonium chloride solution. The layers were separated, and the aqueous layer was extracted with ethyl acetate (3×10 mL). The organic layers were combined, dried (MgSO4), filtered and concentrated. Purification by flash chromatography (19:1 hexane/ethyl acetate) gave E in a yield of 75% (150 mg). 1H NMR (300 MHz, CDCl3): δ 0.8 (t, 3H), 1.25 (narrow m, 20H), 1.4 (s, 3H), 1.6 (2H), 3.6 (t, 3H), 4.2 (q, 2H) and 5.9 (s, 1H).

1. temperatureThe mixture was warmed to 0° C. for 5 minutes
2. temperaturecooled to −78° C
3. temperatureThe solution was then warmed to 0° C.
4. customquenched with a 10% aqueous ammonium chloride solution
5. customThe layers were separated
6. extractionthe aqueous layer was extracted with ethyl acetate (3×10 mL)
7. dry with materialdried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated
10. customPurification by flash chromatography (19:1 hexane/ethyl acetate)
11. customgave E in a yield of 75% (150 mg)

ORD record

ord-a60714a286434f49b63a7a7ecae4f96f

Source dataset

uspto-grants-2012_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08324378B2