Synthesis of Amphetamine Sulphate via Oxime Reduction (Report 2)

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Synthesis of A Sulphate via Oxime Reduction (Report 2)

Previously, a synthesis via aluminum amalgam was carried out with a low yield of the target amine

http://bbzzzsvqcrqtki6umym6itiixfhn...amine-synthesis-via-p2p-oxime-reduction.8562/

The experiments were carried out according to the methods in the articles

Ronald L. Foreman, Frederick P. Siecel, And Robert C. Mrtek Synthesis of Deuterio-l-amphetamine, d1 Sulfate. Journal of Pharmaceutical Sciences, 1969, Vol.58, No. 2, pp. 189-192

James W. Wilson Synthesis of dl-Amphetamine Sulfate Labeled with C14. Journal of the American Pharmaceutical Association, Sci. Ed., 1950, vol. 39, pp. 687-688

The process proceeds according to Scheme 1

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Scheme 1


Starting reagents and materials

  • 22 g р2р
  • 12 g Hydroxylamine hydrochloride + 120 ml H2O
  • 88 ml 4N NaOH
  • 12 ml GAA
  • 1000 ml DCM
  • 50-100 g Na2SO4
  • 100-110 g CaCl2 + 200 ml H2O
  • 70-100 ml 15-20% NaOH
  • 9 g NaBH4
  • 150 ml THF
  • 100 ml IPA
  • 5 ml H2SO4
  • H2O
  • Marquis reagent
  • Flasks
  • Beakers
  • Funnels
  • Termometer
  • Stirrer
  • Heate
  • Paper filter
  • pH-indicator strips

22 p2p with 12 г hydroxylamine hydrochloride in 120-125 ml of water stir at 30-40℃. Fig 0
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Fig 0

Solution of NaOH (88 ml 4N) is added within 70 minutes. Fig 1
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Fig 1



After 70 min, GAA (12 ml) is added to the RM Fig 2
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Fig 2

The pH of the RM should be neutral. Fig 3
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Fig 3


Oxime is extracted with DCM Fig 4
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Fig 4

When exposed to air, the DCM layer turns green. Fig 5
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Fig 5

The DCM layer is washed with a saturated solution of calcium chloride (100-110 g in 200 ml of water) Fig 6
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Fig 6

The DCM layer is dried with sodium sulfate. Fig 7

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Fig 7


Dried layer of DCM Fig 8

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Fig 8

DCM is distilled off Fig 9

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Fig 9

After distillation of DCM, orange oil remains Fig 10

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Fig 10

50 ml of THF is added to the oil Fig 11

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Fig 11

9 g of sodium borohydride are placed in a dry flask. Fig 12

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Fig 12

100 ml of THF is added to the NaBH4 Fig 13

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Fig 13

The oxime solution is added to the NaBH4 in small portions while stirring. Fig 14

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Fig 14

The mixture is stirred for 20 hours Fig 15

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Fig 15

RM is transferred to a large 1000 ml beaker Fig 16

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Fig 16

200 ml of water is added to the RM Fig 17

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Fig 17

A solution of 15-20% NaOH is prepared Fig 18

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Fig 18

70 ml of the prepared solution of 15-20% NaOH is added to the RM Fig 19

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Fig 19

The RM is transferred to a separatory funnel and 200-250 ml of DCM is added. The mixture is mixed well. In case of poor separation, portions of water and DCM are added alternately. Fig 20

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Fig 20

Extraction is carried out 2-3 times. The DCM layer is collected (total volume 600 ml) Fig 21

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Fig 21

DCM is dried with sodium sulfate Fig 22

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Fig 22

The dried DCM is transferred to a distillation flask. Fig 23

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Fig 23

The DCM is distilled off. A yellow oil with an amine smell remains in the flask. Fig 24

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Fig 24

Oil sample tested with Marquis reagent (1 ml 37% formalin + 3-5 ml H2SO4 103%) Fig 25

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Fig 25

A solution of H2SO4 in IPA is prepared. (10 ml of IPA is dried overnight over SiO2) 5 ml of H2SO4 is added to it, the resulting volume of solution is 50 ml Fig 26

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Fig 26

To the obtained oil, after distillation of DCM, 25-40 ml of anhydrous IPA (dried over SiO2) is added. Fig 27

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Fig 27

The resulting solution is poured into a beaker. Fig 28

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Fig 28

The resulting solution is filtered through a paper filter. Fig 29

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Fig 29

The amine solution in IPA should have an alkaline pH. The sulfuric acid solution in IPA should have an acidic pH. Fig 30

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Fig 30

A solution of sulfuric acid is added dropwise to the amine solution in the IPA until a neutral pH is achieved. Fig 31

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Fig 31

The resulting yield was less than 1g. Fig 32

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Fig 32
 
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