1,1'-Carbonyldiimidazole → HCID 54213453, compound

HRID 1085834Notes

Reaction equation

HRID 1085834 reaction equation
[C:1]1([C:7]2[O:11][CH:10]=[N:9][C:8]=2[C:12]([OH:14])=O)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.C(N1C=CN=C1)(N1C=CN=C1)=O.[NH2:27][CH2:28][CH2:29][NH:30][C:31](=[O:37])[O:32][C:33]([CH3:36])([CH3:35])[CH3:34]>O1CCCC1>[C:1]1([C:7]2[O:11][CH:10]=[N:9][C:8]=2[C:12]([NH:27][CH2:28][CH2:29][NH:30][C:31](=[O:37])[O:32][C:33]([CH3:35])([CH3:34])[CH3:36])=[O:14])[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=1

Participants

5

Reactant 3

HCID 682631,1'-CarbonyldiimidazoleHCID 187201N-BOC-ethylenediamineHCID 27762995-Phenyl-1,3-oxazole-4-carboxylic acid

Product 1

HCID 54213453HCID 54213453, compoundYield 92.1%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

3.6 g (19.1 mmol) of 5-phenyl-4-oxazolecarboxylic acid were added portionwise to a suspension of 3.1 g (19.1 mmol) of 1,1'-carbonyldiimidazole in 20 ml of dry tetrahydro-furan, whereby a brown solution formed with o the evolution of gas. After a reaction period of 15 minutes at 20° 3.05 g (19.0 mmol) of t-butyl (2-aminoethyl)carbamate in 10 ml of dry tetrahydrofuran were added dropwise (slight warming) and the reaction mixture was stirred for a further 30 minutes. Thereafter, the reaction mixture was evaporated under reduced pressure and the residue was partitioned between methylene chloride and 0.1 N hydrochloric acid. After washing neutral with saturated sodium chloride solution the organic phase was dried over magnesium sulfate and evaporated, whereby there were obtained 5.8 g (92%) of t-butyl [2-(5-phenyl-4-oxazole- carboxamido)ethyl]- carbamate which were stirred at 20° for 20 minutes in 20 ml of trifluoroacetic acid. Thereafter, the reaction mixture was evaporated under reduced pressure. The residue was dissolved in 5 ml of methanol and treated with 10 ml of 5.5 N hydrogen chloride in methanol. Filtration of the separated crystals yielded 2.4 g (51%) of N-(2-aminoethyl)-5-phenyl-4-oxazole- carboxamide hydrochloride as white crystals, melting point 257° (dec.). The 5-phenyl-4-oxazolecarboxylic acid used as the starting material was prepared as follows: Analogously to the method described in Tetrahedron Letters, 23, 235-236 (1982), from ethyl isocyanoacetate, benzoic acid, phosphoric acid diphenyl ester azide and potassium carbonate in dimethylformamide/water there was prepared ethyl 5-phenyl-4-oxazolecarboxylate which was then converted into the desired acid likewise according to known methods by hydrolysis with 2N sodium hydroxide solution at 50° during 15 minutes.

Workup

  1. customformed with o the evolution of gas
  2. additionwere added dropwise
  3. temperature(slight warming)
  4. customThereafter, the reaction mixture was evaporated under reduced pressure
  5. customthe residue was partitioned between methylene chloride and 0.1 N hydrochloric acid
  6. washAfter washing neutral with saturated sodium chloride solution the organic phase
  7. dry with materialwas dried over magnesium sulfate
  8. customevaporated

Sources & evidence

ORD record
ord-c810f3ecfd4048b38706328f06099387
Source dataset
uspto-grants-1991_04
Patent number
US05011849

Reaction notes

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