Diisopropylamine → (E,E)-5,9,13-Trimethyl-4,8,12-tetradecatrienoic acid, 1,1-dimethylethyl ester

Temperatur

0 °C

To a solution of 9.60 ml (68.5 mmol, 1.5 eq.) of diisopropylamine in 100 ml of THF at -78° C. under argon was added 28.2 ml (45.0 mmol, 1.0 eq.) of 1.6M n-butyllithium in hexanes over 20 minutes. After warming to 0° C. for 15 minutes, the solution was recooled to -78° C. and 6.05 ml (45 mmol, 1.0 eq) of t-butyl acetate was added over 20 minutes. After an additional 15 minutes, 16.0 ml (92 mmol, 2.05 eq.) of hexamethylphosphoramide (HMPA) was added, followed by a solution of 12.53 g (45.0 mmol) of Part A(1) farnesyl bromide in 100 ml of THF over 20 minutes. The reaction was stirred at -78° C. for 2.5 hours, quenched with saturated NH4Cl and allowed to warm to room temperature. After diluting with 400 ml of ethyl acetate, the mixture was washed with four 100 ml portions of water, and 200 ml of brine, dried over MgSO4 and evaporated to provide 12.96 g of crude product as a yellow oil. Purification by flash chromatography on 1 kg of silica gel, eluted with 1:9 ethyl acetate:petroleum ether afforded 9.39 g (65%) of title compound as a pale yellow oil.

1. customwas recooled to -78° C.
2. customquenched with saturated NH4Cl
3. temperatureto warm to room temperature
4. additionAfter diluting with 400 ml of ethyl acetate
5. washthe mixture was washed with four 100 ml portions of water, and 200 ml of brine
6. dry with materialdried over MgSO4
7. customevaporated
8. customto provide 12.96 g of crude product as a yellow oil
9. customPurification by flash chromatography on 1 kg of silica gel
10. washeluted with 1:9 ethyl acetate

ORD-Eintrag

ord-50e9a757c7c14bae8a053e6a577e798d

Quelldatensatz

uspto-grants-1993_12

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05273969