Hydrochloric Acid → trans-5-(2-Amino-1,2,3,4-tetrahydro-6,7-dimethoxy-1-naphthyl)-2-propyl-4-oxazolemethanol

HRID 235092Notes

Reaction equation

HRID 235092 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[C:5]2[C:10](=[CH:11][C:12]=1[O:13][CH3:14])[CH:9]([C:15]1[O:19][C:18]([CH2:20][CH2:21][CH3:22])=[N:17][C:16]=1[CH2:23][O:24]C1CCCCO1)[CH:8]([N+:31]([O-])=O)[CH2:7][CH2:6]2.Cl.C([O-])(O)=O.[Na+]>C(O)C.[Zn]>[NH2:31][C@@H:8]1[CH2:7][CH2:6][C:5]2[C:10](=[CH:11][C:12]([O:13][CH3:14])=[C:3]([O:2][CH3:1])[CH:4]=2)[C@H:9]1[C:15]1[O:19][C:18]([CH2:20][CH2:21][CH3:22])=[N:17][C:16]=1[CH2:23][OH:24]

Participants

6

Reactant 3

HCID 313Hydrochloric AcidHCID 516892Sodium BicarbonateHCID 233535525-(1,2,3,4-Tetrahydro-6,7-dimethoxy-2-nitro-1-naphthyl)-2-propyl-4-(((2-tetrahydropyranyl)oxy)methyl)oxazole

Product 1

HCID 54433255trans-5-(2-Amino-1,2,3,4-tetrahydro-6,7-dimethoxy-1-naphthyl)-2-propyl-4-oxazolemethanolYield 85%

Reagents, catalysts & solvents 2

HCID 23994ZincCatalystHCID 702EthanolSolvent

Procedure

To a solution of the compound from step 29d (1.16 g, 2.52 mmol) in 40 mL of ethanol was added 10 mL of 6 N HCl. The mixture was stirred for 30 min at room temperature, and zinc dust was added in portions until the yellow solution turned colorless. Satd. NaHCO3 solution was added until the mixture was at pH 8-9. The solid was removed by filtration and washed with methylene chloride. The flitrate and washings were combined, dried over MgSO4, concentrated, and purified by chromatography on silica gel, eluting with 5-40% methanol (containing 5%NH4OH) in methylene chloride, to afford 742 mg (85% yield) of the title product as a 1:6.5 mixture of cis:trans isomers. Recrystallization from 1:1 hexane:ethyl acetate provided the pure trans isomer as a solid. MS: 347(M+H)+. NMR (CDCl3) δ:6.62 (s, 1H), 6.29 (s, 1H), 4.62 and 4.52 (abq, J=13 Hz, 2H), 4.02 (d, J=10 Hz, 1H), 3.87 (s, 3H), 3.68 (s, 3H), 3.17 (m, 1H), 3.03-2.79 (m, 2H), 2.65 (t, J=8 Hz, 2H), 2.18 (m, 1H), 1.81 (m, 1H), 1.72 (sx, J=8 Hz, 2H), 0.92 (t, J=8 Hz, 3H).

Workup

  1. customThe solid was removed by filtration
  2. washwashed with methylene chloride
  3. dry with materialdried over MgSO4
  4. concentrationconcentrated
  5. custompurified by chromatography on silica gel
  6. washeluting with 5-40% methanol (containing 5%NH4OH) in methylene chloride

Sources & evidence

ORD record
ord-ad877b1fb77f4e28b0466fa317dc4851
Source dataset
uspto-grants-1997_01
Patent number
US05597832

Reaction notes

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