Allylamine → Allyl-(2-methyl-pent-4-enyl)-amine

To a solution of 2-methyl-pent-4-enoic acid ethyl ester (7.1 g, 50 mmol) was added dropwise a solution of DIBAL (1.0 M in hexanes, 75 ml) at −78 C. over 1.0 h. After the addition, the reaction mixture was stirred at −78 C. for another hour. The reaction was quenched with saturated NH4Cl (10 ml) and 4% HCl, then was extracted with EtOAc (3×100 ml). The combined organic extracts were dried with MgSO4, filtered, concentrated by rotary evaporation and the crude reaction product was used in the next reaction without further purification. 2-Methyl-4-pentenal (3.3 g, 33.7 mmol) was dissolved in CH2Cl2 (100 ml). To this solution allylamine (2.9 g, 50.5 mmol) was added. Molecular sieves (5 g) were used to absorb water generated during the reaction. The mixture was stirred at room temperature over night. The reaction mixture was concentrated by rotary evaporation and the crude product was used in the next reaction without further purification. Allyl-(2-methyl-pent-4-enylidene)-amine (3.2 g, 23.4 mmol) was diluted in 50 ml MeOH. To the solution NaBH4 (1.0 g, 26.3 mmol) was added at 0° C. After addition the mixture was stirred at RT for 5 h. The reaction mixture was concentrated and the residue was partitioned between EtOAc/20% aq. NaOH. The organic layer was dried over Na2SO4, fitered and concentrated by rotary evaporation to give allyl-(2-methyl-pent-4-enyl)-amine (1.5 g 48% yield): 1H-NMR (400 Hz, CDCl3): d=5.93–5.68 (m, 2H), 5.18–4.92(m, 4H), 3.21 (d, 2H), 2.60–2.40(m, 2H), 1.97–1.65(m, 2H), 0.92(d, 3H).

1. additionAfter the addition
2. waitfor another hour
3. customThe reaction was quenched with saturated NH4Cl (10 ml) and 4% HCl
4. extractionwas extracted with EtOAc (3×100 ml)
5. dry with materialThe combined organic extracts were dried with MgSO4
6. filtrationfiltered
7. concentrationconcentrated by rotary evaporation
8. customthe crude reaction product
9. customwas used in the next reaction without further purification
10. customto absorb water
11. customgenerated during the reaction
12. stirringThe mixture was stirred at room temperature over night
13. concentrationThe reaction mixture was concentrated by rotary evaporation
14. customthe crude product was used in the next reaction without further purification
15. additionAfter addition the mixture
16. stirringwas stirred at RT for 5 h
17. concentrationThe reaction mixture was concentrated
18. customthe residue was partitioned between EtOAc/20% aq. NaOH
19. dry with materialThe organic layer was dried over Na2SO4
20. concentrationfitered and concentrated by rotary evaporation

ORD record

ord-0018e7c764c94e929c9a3b0168b96f0d

Source dataset

uspto-grants-2006_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07071184B2