Hydrochloric Acid → 1-(Pyridin-2-yl)cyclopropanamine

Temperature

-78 °C

In a nitrogen-atmosphere, to a solution of 1.0 g of 2-cyanopyridine and 3.0 g of titanium tetraisopropoxide in 14 mL of diethyl ether, 20 mL of ethyl magnesium bromide (in a 0.96 M tetrahydrofuran solution) was dropped while stirring the solution at −78° C. After the completion of the dropping, the resultant mixture was stirred at room temperature for 1 hour. Next, to the reaction mixture, 2.7 g of a trifluoroboron diethyl ether complex was added and the stirring of the reaction mixture was continued for another 18 hours in a nitrogen-atmosphere at room temperature. After the completion of the reaction, to the reaction mixture, 20 mL of a 1N hydrochloric acid aqueous solution was added and the resultant mixture was stirred for 10 minutes. Next, 30 mL of a 1N sodium hydroxide aqueous solution was added to the reaction mixture while ice-cooling the mixture to convert the mixture to basic and thereafter, the reaction mixture was extracted with diethyl ether (50 mL×2). The organic phase was dehydrated and dried with saturated brine and over anhydrous sodium sulfate, respectively, in this order, and the solvent was distilled off under reduced pressure to obtain 1.0 g of crude 1-(2-pyridyl)cyclopropylamine as a yellow oily substance. This substance was used in the reaction as it is without further purification.

1. additionNext, to the reaction mixture, 2.7 g of a trifluoroboron diethyl ether complex was added
2. stirringthe stirring of the reaction mixture
3. customAfter the completion of the reaction
4. temperaturecooling the mixture
5. extractionwas extracted with diethyl ether (50 mL×2)
6. dry with materialdried with saturated brine and over anhydrous sodium sulfate
7. distillationrespectively, in this order, and the solvent was distilled off under reduced pressure

ORD record

ord-514295f209f54fd0abb8d1e5c87126c1

Source dataset

uspto-grants-2012_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08119671B2