Water → 3-Benzyl-8-methoxy-1,2,3,4-tetrahydro-chromeno[3,4-c]pyridin-5-one

HRID 962631Notes

Reaction equation

HRID 962631 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=C(O)[CH:6]=[CH:7][CH:8]=1.Cl.[CH2:11]([N:18]1[CH2:23][CH2:22][C:21](=O)[CH:20]([C:25]([O:27][CH3:28])=[O:26])[CH2:19]1)[C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1.O.[OH-].[NH4+]>S(=O)(=O)(O)O>[CH2:11]([N:18]1[CH2:23][CH2:22][C:21]2[C:6]3[CH:7]=[CH:8][C:3]([O:2][CH3:1])=[CH:4][C:28]=3[O:27][C:25](=[O:26])[C:20]=2[CH2:19]1)[C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1

Participants

6

Reactant 4

HCID 962WaterHCID 90073-MethoxyphenolHCID 14923Ammonium Hydroxide2×HCID 107479Methyl 1-benzyl-4-oxopiperidine-3-carboxylate hydrochloride

Product 1

HCID 98835873-Benzyl-8-methoxy-1,2,3,4-tetrahydro-chromeno[3,4-c]pyridin-5-oneYield 47.1%

Reagents, catalysts & solvents 1

HCID 1118Sulfuric AcidSolvent

Procedure

A mixture of 3-methoxyphenol (28.3 g, 227 mmol) and methyl 1-benzyl-4-oxo-3-piperidinecarboxylate hydrochloride (46.1 g, 162 mmol) is cooled in ice and treated dropwise with a solution prepared from 38 mL of water diluted to 150 mL with concentrated sulfuric acid. The mixture is stirred at room temperature for 48 hours, then added slowly to 500 g of ice and 100 mL of concentrated ammonium hydroxide. Additional ice and ammonium hydroxide are added until the pH of the mixture is 10 to 11. Stirring is continued until the initially gummy precipitate becomes granular. The solid is filtered, then stirred in 400 mL of 2.5% aqueous sodium hydroxide solution followed by 400 mL of 10% methanol in water. The solid is again filtered and recrystallized from 2-propanol to yield 24.5 g (47%) of final product; mp 118°-120° C.

Workup

  1. temperatureis cooled in ice
  2. additiontreated dropwise with a solution
  3. stirringStirring
  4. filtrationThe solid is filtered
  5. stirringstirred in 400 mL of 2.5% aqueous sodium hydroxide solution
  6. filtrationThe solid is again filtered
  7. customrecrystallized from 2-propanol

Sources & evidence

ORD record
ord-fa26d66f7ec6403fb40b810203daa152
Source dataset
uspto-grants-1998_06
Patent number
US05760050

Reaction notes

Loading…