Hydrogen Bromide → 3-Hydroxy-4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridinium bromide

HRID 1155342Notes

Reaction equation

HRID 1155342 reaction equation
[OH:1][C:2]1[C:10]2[CH2:9][CH2:8][N:7](C(OC)=O)[CH2:6][C:5]=2[O:4][N:3]=1.[BrH:15].[K+].[Br-].CO>C(O)(=O)C>[Br-:15].[OH:1][C:2]1[C:10]2[CH2:9][CH2:8][NH:7][CH2:6][C:5]=2[O:4][NH+:3]=1

Participants

6

Reactant 4

HCID 260Hydrogen BromideHCID 887MethanolHCID 253877Potassium BromideHCID 178501908HCID 178501908, compound

Product 1

HCID 700825683-Hydroxy-4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridinium bromide

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

A solution of methyl 3-hydroxy-4,5,6,7-tetrahydroisoxazolo[5, 4-c]-pyridine-6-carboxylate (309 mg; 1.6 mmol) in a solution of hydrogen bromide in glacial acetic acid (3 ml; 43%) was refluxed for 15 minutes. Upon evaporation to dryness in vacuo the residue was treated with the same reagent (3 ml) for further 15 minutes. Evaporation of the reaction mixture to dryness in vacuo and recrystallization (methanol-ether) of the residue gave Ia (salt) (193 mg; 56%) as faintly reddish crystals, m.p. 162-163° C. (decomp.). IR (KBr): 3700-3300 (m), 3070 (s), 3000-2300 (several bands, m-s), 1670 (m), 1580 (m), 1525 (s), 1505 (w) cm-1. UV (methanol): <210 nm. 1H NMR [D2O (sodium 3-(trimethylsilyl) propanesulfonate was used as an internal standard)]: δ4.77 (ca. 5 H, s), 4.43 (2 H, t, J 1 Hz), 3.7- 3.4 (2 H, q, J 6 and 7 Hz), 3.0-2.7 (2 H, t).

Workup

  1. customUpon evaporation to dryness in vacuo the residue
  2. additionwas treated with the same reagent (3 ml) for further 15 minutes
  3. customEvaporation of the reaction mixture to dryness
  4. customin vacuo and recrystallization (methanol-ether) of the residue
  5. customgave Ia (salt) (193 mg; 56%) as faintly reddish crystals, m.p. 162-163° C. (decomp.)

Sources & evidence

ORD record
ord-eaa2bb7851074f4cb58f61a46e6f16fd
Source dataset
uspto-grants-1981_11
Patent number
US04301287

Reaction notes

Loading…