Hydrochloric Acid → 8,9-Dimethoxy-1,2,3,11b-tetrahydrochromeno[4,3,2-de]isoquinoline

HRID 2227367Notes

Reaction equation

HRID 2227367 reaction equation
[CH3:1][O:2][C:3]1[C:8]2[O:9][C:10]3[C:11]4[C:16]([CH:17]=[CH:18][CH:19]=3)=[CH:15][N:14]=[CH:13][C:12]=4[C:7]=2[CH:6]=[CH:5][C:4]=1[O:20][CH3:21].Cl>[Pt](=O)=O.C(O)(=O)C>[CH3:1][O:2][C:3]1[C:8]2[O:9][C:10]3[C:11]4[CH:12]([CH2:13][NH:14][CH2:15][C:16]=4[CH:17]=[CH:18][CH:19]=3)[C:7]=2[CH:6]=[CH:5][C:4]=1[O:20][CH3:21]

Participants

5

Reactant 2

HCID 313Hydrochloric AcidHCID 129719218,9-Dimethoxychromeno[4,3,2-de]isoquinoline

Product 1

HCID 129719228,9-Dimethoxy-1,2,3,11b-tetrahydrochromeno[4,3,2-de]isoquinoline

Reagents, catalysts & solvents 2

HCID 345198Adams' catalystCatalystHCID 176Acetic AcidSolvent

Procedure

Platinum (IV) oxide (200 mg) was added to a solution containing 50 ml of acetic acid and isoquinoline 6 (1 g; 3.5 mmol). After adding 2.8 ml of concentrated HCl, the mixture was shaken on a Parr hydrogenator at 60 psi for 24 hours. The green solution was filtered through Celite to remove the catalyst and the majority of the acetic acid was removed by rotary evaporation. The remaining acid was neutralized using a saturated sodium bicarbonate solution, extracted with diethyl ether (3×250 ml), dried (Na2SO4), and concentrated. The resulting oil (0.997 g; 99%) was used without further purification: 1H NMR: (300 MHz, CDCl3): 7.10 (t, 1H, J=7.5 Hz); 7.00 (d, 1H, J=8.4 Hz); 6.78 (m, 2H); 6.60 (d, 1H, J=9 Hz); 4.10 (s, 2H); 3.84 (m, 8H); 2.93 (t, 1H, J=12.9 Hz).

Workup

  1. filtrationThe green solution was filtered through Celite
  2. customto remove the catalyst
  3. customthe majority of the acetic acid was removed by rotary evaporation
  4. extractionextracted with diethyl ether (3×250 ml)
  5. dry with materialdried (Na2SO4)
  6. concentrationconcentrated
  7. customThe resulting oil (0.997 g; 99%) was used without further purification

Sources & evidence

ORD record
ord-e7c7e0537fe64d6498d8035404a1bcd2
Source dataset
uspto-grants-2002_07
Patent number
US06413977B1

Reaction notes

Loading…