Lithium hydroxide, monohydrate → 1-(4-Hydroxymethyl-benzyl)-1H-pyrazole-4-carboxylic acid

HRID 928392Notes

Reaction equation

HRID 928392 reaction equation
C([O:3][C:4]([C:6]1[CH:7]=[N:8][N:9]([CH2:11][C:12]2[CH:17]=[CH:16][C:15]([C:18](C)(C)[O:19][SiH2]C(C)(C)C)=[CH:14][CH:13]=2)[CH:10]=1)=[O:5])C.O.[OH-].[Li+]>CO.O>[OH:19][CH2:18][C:15]1[CH:16]=[CH:17][C:12]([CH2:11][N:9]2[CH:10]=[C:6]([C:4]([OH:5])=[O:3])[CH:7]=[N:8]2)=[CH:13][CH:14]=1

Participants

5

Reactant 2

HCID 168937Lithium hydroxide, monohydrateHCID 1317350591-[4-(tert-Butyl-dimethyl-silanyloxymethyl)-benzyl]-1H-pyrazole-4-carboxylic acid ethyl ester

Product 1

HCID 580812341-(4-Hydroxymethyl-benzyl)-1H-pyrazole-4-carboxylic acid

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 962WaterSolvent

Procedure

A mixture of 1-[4-(tert-Butyl-dimethyl-silanyloxymethyl)-benzyl]-1H-pyrazole-4-carboxylic acid ethyl ester (630 mg, 1.4 mmol) and lithiumhydroxide-hydrate (119 mg, 2.8 mmol) in 20 mL MeOH and 10 mL water was stirred at RT for 32 h. The mixture was evaporated in vacuo and the aq. layer was acidified with 1 N aq. HCl. After extraction with ethyl acetate, the organic layer was dried over MgSO4 and evaporated to yield the crude product which was used in the next step without further purification. 1H-NMR (DMSO-d6, 400 MHz) 12.3 (bs, 1H), 8.36 (s, 1H), 7.81 (s, 1H), 7.23-7.31 (s, 4H), 5.34 (s, 2H), 5.18 (t, 1H), 4.47 (s, 2H).

Workup

  1. customThe mixture was evaporated in vacuo
  2. extractionAfter extraction with ethyl acetate
  3. dry with materialthe organic layer was dried over MgSO4
  4. customevaporated

Sources & evidence

ORD record
ord-65ad00588a5c4a5aa9b3ac02b3d281a9
Source dataset
uspto-grants-2016_03
Patent number
US09290485B2

Reaction notes

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