Hydrochloric Acid → 1-Trityl-1H-imidazole-4-carboxylic acid

3H-Imidazole-4-carboxylic acid methyl ester (9.86 g, 78.2 mmol) is taken up in 150 mL DCM, triethylamine (11.9 mL, 86.0 mmol) is added and the reaction mixture is stirred for 5 min at RT. Chlorotriphenylmethane (24.0 g, 86.0 mmol) is added and the reaction mixture is stirred overnight at RT. The reaction mixture is extracted with an aqueous 5% NaHCO3 solution, the organic phase is dried over MgSO4 and concentrated under reduced pressure. The residue (20.7 g) is taken up in 100 mL MeOH, a solution of lithium hydroxide (4.80 g, 24.0 mmol) in 20 mL water is added drop wise and the reaction mixture is stirred over weekend at RT. The reaction mixture is acidified to pH 4 with 6N hydrochloric acid, 200 mL DCM is added and the two phase mixture is stirred vigorously. The phases are separated and the organic phase is dried over MgSO4 and concentrated under reduced pressure. Yield: 19.2 g. HPLC-MS: double peak tR=2.55/2.67 min, (M−H)−=353.

1. stirringthe reaction mixture is stirred overnight at RT
2. extractionThe reaction mixture is extracted with an aqueous 5% NaHCO3 solution
3. dry with materialthe organic phase is dried over MgSO4
4. concentrationconcentrated under reduced pressure
5. stirringthe reaction mixture is stirred over weekend at RT
6. additionis added
7. stirringthe two phase mixture is stirred vigorously
8. customThe phases are separated
9. dry with materialthe organic phase is dried over MgSO4
10. concentrationconcentrated under reduced pressure
11. custom2.67 min, (M−H)−=353

ORD record

ord-ae7d40e5f3a74283aa13cd17a97c1e6b

Source dataset

uspto-grants-2012_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08288379B2