Butyric Acid → 4697-92-1

Butyric acid (1.8 g, 19.4 mmol), 1,3-diaminopropane (0.60 g, 8.1 mmol), 1-hydroxybenzotriazole monohydrate (HOBt) (2.4 g, 17.8 mmol) was dissolved in anhydrous DMF (30 mL). 1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide hydrochloride (EDC.HCl) (3.4 g, 17.8 mmol) was added in small portions at 0° C. and the resulting solution left stirring at room temperature for 15 h. After evaporation of DMF, the solution was taken up with CHCl3 (200 mL) and was washed successively with a 1 M aqueous NaHCO3 solution (30 mL), a 0.1 M aqueous HCl solution (30 mL) abd brine (30 mL). Then the organic layer was dried with anhydrous Na2SO4 and the solvent was removed by rotary evaporation. The resulting residue was precipitated using ether and used in next reaction without further purification. To the precipitate dissolved in THF (50 mL), LiAlH4 (0.40 g, 10.6 mmol) was added slowly at 0° C. The mixture was refluxed overnight, quenched carefully with 0.4 mL of water, 0.4 mL of 15% NaOH and 1.2 mL of water. After filtration on celite, the filtrate was evaporated, dissolved in DCM (100 mL) and extracted with 1N NaOH solution (50 mL). The organic layer dried with anhydrous Na2SO4. The residue was purified by silica gel column chromatography (MeOH/CH2Cl2) providing N,N′-dibutyl-1,3-propanediamine as an oil (0.90 g, 52% (two steps)). 1H NMR (300 MHz, CDCl3): δ 2.67 (t, J=7.0 Hz, 4H), 2.59 (t, J=7.0 Hz, 4H), 1.69 (quin, J=7.0 Hz, 2H), 1.52-1.39 (m, 4H), 1.39-1.24 (m, 4H), 0.91 (t, J=7.2 Hz, 6H); 13C NMR (75 MHz, CDCl3): δ 50.1, 48.9, 32.5, 30.7, 20.7, 14.2; HRMS (ESI): calcd. for C11H26N2[M+H]+ 187.2169. found 187.2170.

1. waitthe resulting solution left
2. customAfter evaporation of DMF
3. washwas washed successively with a 1 M aqueous NaHCO3 solution (30 mL)
4. dry with materialThen the organic layer was dried with anhydrous Na2SO4
5. customthe solvent was removed by rotary evaporation
6. customThe resulting residue was precipitated
7. customused in next reaction without further purification
8. temperatureThe mixture was refluxed overnight
9. customquenched carefully with 0.4 mL of water, 0.4 mL of 15% NaOH and 1.2 mL of water
10. filtrationAfter filtration on celite
11. customthe filtrate was evaporated
12. dissolutiondissolved in DCM (100 mL)
13. extractionextracted with 1N NaOH solution (50 mL)
14. dry with materialThe organic layer dried with anhydrous Na2SO4
15. customThe residue was purified by silica gel column chromatography (MeOH/CH2Cl2)

ORD record

ord-81d228fc777d404691cb44a9ff2842e2

Source dataset

uspto-grants-2014_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08815263B2