3,4-Dimethoxy-1,2,5-thiadiazole 1-oxide → Tetrahydroisoquinoline thiadiazole-1-oxide

HRID 463525Notes

Reaction equation

HRID 463525 reaction equation
[NH2:1][CH2:2][CH2:3]CO[C:6]1[CH:15]=[C:14]2[C:9]([CH2:10][CH2:11][N:12](C)[CH2:13]2)=[CH:8][CH:7]=1.COC1C(OC)=N[S:21](=[O:26])[N:20]=1>CO>[S:21]1(=[O:26])[CH:3]=[CH:2][N:1]=[N:20]1.[CH2:13]1[C:14]2[C:9](=[CH:8][CH:7]=[CH:6][CH:15]=2)[CH2:10][CH2:11][NH:12]1

Participants

4

Reactant 2

HCID 129139473,4-Dimethoxy-1,2,5-thiadiazole 1-oxideHCID 135411037-(3-Aminopropoxy)-2-methyl-1,2,3,4-tetrahydroisoquinoline

Product 1

HCID 70395437Tetrahydroisoquinoline thiadiazole-1-oxide

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent2×

Procedure

A solution of 7-(3-aminopropoxy)-2-methyl-1,2,3,4-tetrahydroisoquinoline (5.43 g) in methanol (70 ml) is slowly added over a period of 45 minutes to a stirred solution of 3,4-dimethoxy-1,2,5-thiadiazole-1-oxide (3.68 g) in 375 ml of methanol at a temperature of 3° C. The reaction mixture is stirred for an additional one hour and 25.0 g anhydrous ammonia is bubbled in over a period of 10 minutes. The resulting mixture is warmed to RT with stirring and the solution is evaporated in vacuo. The near-white solid residue is dissolved in hot 95% ethanol, filtered hot and rinsed with hot ethanol. The solution is cooled with stirring, then stirred in an ice bath for 30 minutes and filtered. The resulting solid is washed with cold ethanol and diethyl ether and dried in air, giving the desired tetrahydroisoquinoline thiadiazole-1-oxide as a white powder, M.P. 193°-194° C.

Workup

  1. custom25.0 g anhydrous ammonia is bubbled in over a period of 10 minutes
  2. stirringwith stirring
  3. customthe solution is evaporated in vacuo
  4. dissolutionThe near-white solid residue is dissolved in hot 95% ethanol
  5. filtrationfiltered hot
  6. washrinsed with hot ethanol
  7. temperatureThe solution is cooled
  8. stirringwith stirring
  9. stirringstirred in an ice bath for 30 minutes
  10. filtrationfiltered
  11. washThe resulting solid is washed with cold ethanol and diethyl ether
  12. customdried in air

Sources & evidence

ORD record
ord-ede7e1e56dfe4e29bb48535b3f0657d4
Source dataset
uspto-grants-1985_05
Patent number
US04520025

Reaction notes

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