Diisopropylamine → HCID 13596438, compound

Temperature

-10 °C

To a solution of 1.5 ml of diisopropylamine in 75 ml of tetrahydrofuran were added dropwise 135 ml of 1.5 M solution of butyl lithium in hexane, 75 ml of hexamethylphosphoramide (HMPA) and 6.15 ml of propiolic acid, successively, at -50° C., the mixture was allowed to heat to -10° C. over a period of 2 hours. To it was added dropwise 27.2 ml of 1,5-dibromopentane at -25° to -30° C., the solution allowed to heat to room temperature over a period of 2 hours, and stirred for one hour. The reaction mixture was poured into 500 ml of ice-water, extracted with methylene chloride, the extract washed with a saturated aqueous solution of sodium chloride, dried over sodium sulphate and concentrated under reduced pressure. The residue was dissolved in diethyl ether, there was added diazomethane-etherate until the solution was coloured pale yellow. After concentration under reduced pressure, the residue was purified by column chromatography on silica gel using chloroform as eluent to give 4.05 g of the subtitle compound having the following physical characteristics:

1. customat -50° C.
2. temperatureto heat to room temperature over a period of 2 hours
3. extractionextracted with methylene chloride
4. washthe extract washed with a saturated aqueous solution of sodium chloride
5. dry with materialdried over sodium sulphate
6. concentrationconcentrated under reduced pressure
7. dissolutionThe residue was dissolved in diethyl ether
8. additionthere was added diazomethane-etherate until the solution
9. concentrationAfter concentration under reduced pressure
10. customthe residue was purified by column chromatography on silica gel

ORD record

ord-7fbb475608fa4975941fece4535f6aa8

Source dataset

uspto-grants-1981_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04256757