Sodium Hydroxide → 1-(3,4-Dihydro-2H-chromen-3-yl)methanamine hydrochloride

HRID 1196003Notes

Reaction equation

HRID 1196003 reaction equation
[Cl-:1].[Al+3].[Cl-].[Cl-].[H-].[Al+3].[Li+].[H-].[H-].[H-].[C:11]([C:13]1[CH2:14][O:15][C:16]2[C:21]([CH:22]=1)=[CH:20][CH:19]=[CH:18][CH:17]=2)#[N:12].[OH-].[Na+]>C(OCC)C.O1CCCC1.O>[ClH:1].[NH2:12][CH2:11][CH:13]1[CH2:22][C:21]2[C:16](=[CH:17][CH:18]=[CH:19][CH:20]=2)[O:15][CH2:14]1

Participants

8

Reactant 4

HCID 14798Sodium HydroxideHCID 424382H-1-Benzopyran-3-carbonitrileHCID 6451240Aluminum(III) ChlorideHCID 21226445Aluminium lithium hydride

Product 1

HCID 162323681-(3,4-Dihydro-2H-chromen-3-yl)methanamine hydrochloride

Reagents, catalysts & solvents 3

HCID 962WaterSolvent2×HCID 3283Diethyl EtherSolvent2×HCID 8028TetrahydrofuranSolvent

Procedure

First 1.77 g (13.32 mmol) of aluminium chloride in 50 ml of absolute diethyl ether are added dropwise while stirring at room temperature to a suspension of 3.04 g (80 mmol) of lithium aluminium hydride in 100 ml of absolute diethyl ether. Then 6.29 g (40 mmol) of 3-cyanochromene [R. C. Gupta et al., Ind. J. Chem. 21B, 344 (1982)] in 50 ml of absolute tetrahydrofuran are added dropwise within a period of 20 minutes. The reaction mixture is boiled under reflux for 16 hours. After it has cooled, it is carefully decomposed with 3.1 ml of water, 3.1 ml of sodium hydroxide solution (15% strength) and 9.3 ml of water. The precipitate formed is filtered off with suction, the filtrate is concentrated by evaporation in vacuo and the oily residue is dissolved in diethyl ether. The organic phase is washed with water and extracted with 2N hydrochloric acid. The combined hydrochloric acid extracts are rendered alkaline, while cold, with sodium hydroxide solution (30% strength) and extracted by shaking with dichloromethane. After drying the combined organic phases over sodium sulphate and concentrating in vacuo, 3.5 g (53.6%) of 3-aminomethylchroman are obtained in the form of a yellow oil. The 3-aminomethylchroman hydrochloride produced therefrom using hydrochloric acid in diethyl ether is recrystallised from methanol/diethyl ether and melts at 218°-219°.

Workup

  1. temperatureunder reflux for 16 hours
  2. temperatureAfter it has cooled
  3. customThe precipitate formed
  4. filtrationis filtered off with suction
  5. concentrationthe filtrate is concentrated by evaporation in vacuo
  6. dissolutionthe oily residue is dissolved in diethyl ether
  7. washThe organic phase is washed with water
  8. extractionextracted with 2N hydrochloric acid
  9. extractionwhile cold, with sodium hydroxide solution (30% strength) and extracted
  10. dry with materialAfter drying the combined organic phases over sodium sulphate
  11. concentrationconcentrating in vacuo, 3.5 g (53.6%) of 3-aminomethylchroman
  12. customare obtained in the form of a yellow oil

Sources & evidence

ORD record
ord-e34e3e2fe13245c783b78cd166aaccc4
Source dataset
uspto-grants-1992_05
Patent number
US05112855

Reaction notes

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