4-Hydroxybenzaldehyde → Methyl 1-(4-hydroxybenzyl)-1,2,5,6-tetrahydropyridine-3-carboxylate hydrochloride

HRID 1732569

Reaction equation

HRID 1732569 reaction equation
[OH:1][C:2]1[CH:9]=[CH:8][C:5]([CH:6]=O)=[CH:4][CH:3]=1.C([BH3-])#N.[Na+].[ClH:14].[NH:15]1[CH2:20][CH2:19][CH:18]=[C:17]([C:21]([O:23][CH3:24])=[O:22])[CH2:16]1.Cl>CO.CC(C)=O>[ClH:14].[OH:1][C:2]1[CH:9]=[CH:8][C:5]([CH2:6][N:15]2[CH2:20][CH2:19][CH:18]=[C:17]([C:21]([O:23][CH3:24])=[O:22])[CH2:16]2)=[CH:4][CH:3]=1

Participants

7

Reactant 4

HCID 1264-HydroxybenzaldehydeHCID 313Hydrochloric AcidHCID 201540Norarecoline HydrochlorideHCID 5003444Sodium cyanoborohydride

Product 1

HCID 12769335Methyl 1-(4-hydroxybenzyl)-1,2,5,6-tetrahydropyridine-3-carboxylate hydrochlorideYield 65.8%

Reagents, catalysts & solvents 2

HCID 180AcetoneSolventHCID 887MethanolSolvent

Conditions

Temperature
25 °C

Procedure

4-Hydroxybenzaldehyde (1.34 g.) and sodium cyanoborohydride (0.7 g.) were added to a solution of methyl 1,2,5,6-tetrahydropyridine-3-carboxylate hydrochloride (3.1 g.) in methanol (30 ml.). The mixture was stirred for 3 days at 25° C., evaporated and water (30 ml.) added to the residue followed by concentrated hydrochloric acid to pH 1. This mixture was extracted with ether (2×20 ml.) and the extracts discarded. The aqueous phase was basified to pH 9 with 10% w/v sodium carbonate solution and then extracted with ether (2×30 ml.). The combined extracts were dried (MgSO4) and evaporated. The oil obtained was dissolved in acetone and treated with a slight excess of ethereal hydrogen chloride. The solid which was precipitated was collected by filtration to give methyl 1-(4-hydroxybenzyl)-1,2,5,6-tetrahydropyridine-3-carboxylate hydrochloride (2.05 g.). A portion was recrystallised from methanol and acetone to give pure material of m.p. 212°-214° C. (dec.).

Workup

  1. customevaporated
  2. additionwater (30 ml.) added to the residue
  3. extractionThis mixture was extracted with ether (2×20 ml.)
  4. extractionextracted with ether (2×30 ml.)
  5. dry with materialThe combined extracts were dried (MgSO4)
  6. customevaporated
  7. customThe oil obtained
  8. customThe solid which was precipitated
  9. filtrationwas collected by filtration

Sources & evidence

ORD record
ord-e8a43c1ee1a544ec971435893d5c4d7b
Source dataset
uspto-grants-1980_12
Patent number
US04238488

Linked notes

Loading…