Imidazole → 5-(2-Iodo-ethyl)-2-pentyl-benzoxazole

HRID 1170412Notes

Reaction equation

HRID 1170412 reaction equation
[CH2:1]([C:6]1[O:7][C:8]2[CH:14]=[CH:13][C:12]([CH2:15][CH2:16]O)=[CH:11][C:9]=2[N:10]=1)[CH2:2][CH2:3][CH2:4][CH3:5].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.N1C=CN=C1.[I-:42].Cl.[NH4+]>C1COCC1.C(OCC)C>[I:42][CH2:16][CH2:15][C:12]1[CH:13]=[CH:14][C:8]2[O:7][C:6]([CH2:1][CH2:2][CH2:3][CH2:4][CH3:5])=[N:10][C:9]=2[CH:11]=1

Participants

8

Reactant 5

HCID 795ImidazoleHCID 11776TriphenylphosphineHCID 30165Iodide IonHCID 21905121Ammonium hydrochlorideHCID 68769861HCID 68769861, compound

Product 1

HCID 687659935-(2-Iodo-ethyl)-2-pentyl-benzoxazole

Reagents, catalysts & solvents 2

HCID 3283Diethyl EtherSolventHCID 8028TetrahydrofuranSolvent

Conditions

Temperature
0 °C

Procedure

Under an argon atmosphere, a 0° C. solution of 2-(2-pentyl-benzoxazol-5-yl)-ethanol (1.63 g, 6.99 mmol) in dry THF (49 ml) was treated with triphenyl phosphine (2.018 b, 7.693 mmol) and imidazole (1.05 g, 15.38 mmol). After complete dissolution iodide (1.95 g, 7.69 mmol) was added in small portion so that the reaction temperature never exceeded 4° C. After stirring for 3 hours at 0° C. the reaction mixture was distributed between diethyl ether and saturated aqueous ammonium hydrochloride. The organic layer was evaporated in vacuum, suspended in diethyl ether, filtered and the filtrate concentrated in vacuum. Silica gel chromatography (eluent: pentane/diethyl ether 4/1) followed by crystallization from pentane provided the title compound as colorless crystals. mp: 47.7/48.7° C.

Workup

  1. additionwas added in small portion so that the reaction temperature never exceeded 4° C
  2. customThe organic layer was evaporated in vacuum
  3. filtrationfiltered
  4. concentrationthe filtrate concentrated in vacuum
  5. customSilica gel chromatography (eluent: pentane/diethyl ether 4/1) followed by crystallization from pentane

Sources & evidence

ORD record
ord-015391dce58d41cc9149c0213f1e5c14
Source dataset
uspto-grants-2010_11
Patent number
US07825260B2

Reaction notes

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