O-Phenylenediamine → 2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-benzimidazole

HRID 2309616Notes

Reaction equation

HRID 2309616 reaction equation
Cl.[C:2]1([CH2:8][N:9]2[CH2:14][CH2:13][CH:12]([CH2:15][C:16](O)=O)[CH2:11][CH2:10]2)[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[C:19]1([NH2:26])[C:20]([NH2:25])=[CH:21][CH:22]=[CH:23][CH:24]=1.[OH-].[K+]>O>[C:2]1([CH2:8][N:9]2[CH2:14][CH2:13][CH:12]([CH2:15][C:16]3[NH:26][C:19]4[CH:24]=[CH:23][CH:22]=[CH:21][C:20]=4[N:25]=3)[CH2:11][CH2:10]2)[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

5

Reactant 3

HCID 7243O-PhenylenediamineHCID 14797Potassium HydroxideHCID 140128442-(1-Benzylpiperidin-4-yl)acetic acid hydrochloride

Product 1

HCID 140128452-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-benzimidazole

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

To 73 parts of hot (70° C.) polyphosphoric acid were added 27 parts of 1-(phenylmethyl)-4-piperidineacetic acid hydrochloride: temperature rose to 100° C. When the addition was complete, there were added portionwise 14 parts of 1,2-benzenediamine and stirring and heating was continued for 50 minutes at 170° C. The hot reaction mixture was poured into 300 parts of warm water. The acid solution was alkalized with a potassium hydroxide solution. The precipitated free base was filtered off, washed with water and extracted with trichloromethane. The extract was dried and evaporated. The solid residue was recrystallized from a mixture of 2-propanone and methanol, yielding 17 parts of 2-[[1-(phenylmethyl)-4-piperidinyl]methyl]-1H-benzimidazole; mp. 221.5°-222° C. (compound 1).

Workup

  1. customrose to 100° C
  2. additionWhen the addition
  3. temperatureheating
  4. filtrationThe precipitated free base was filtered off
  5. washwashed with water
  6. extractionextracted with trichloromethane
  7. customThe extract was dried
  8. customevaporated
  9. customThe solid residue was recrystallized from a mixture of 2-propanone and methanol

Sources & evidence

ORD record
ord-015bdc4084a44e71955ede5b633b1c6d
Source dataset
uspto-grants-1987_09
Patent number
US04695575

Reaction notes

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