Réaction #58005

Équation de réaction

alcohol

tert-butyl 4-{2-[(1R)-1-hydroxypropyl]-4,5-dimethylphenyl)-3,6-dihydropyridine-1(2H)-carboxylate

triphenylphosphine

imidazole

→

azide

tert-butyl 4-{2-[(1S)-1-hydroxypropyl]-4,5-dimethylphenyl}-3,6-dihydropyridine-1(2H)-carboxylate

Solvants

DCM

Conditions de réaction

Traitement

1. 1
   Autre2Py (prepared
2. 2
   workup.ADDITIONAfter the addition
3. 3
   FiltrationThe reaction mixture was filtered through a short column of silica gel
4. 4
   Lavageeluted with the appropriate volume of DCM
5. 5
   Autreto remove excess salts and polar byproducts
6. 6
   ConcentrationThe filtrate was concentrated in vacuo
7. 7
   Autrethe crude residue purified by flash chromatography on silica gel (gradient elution; 0%-20% EtOAc/hexanes as eluent)

Mode opératoire

Diisopropylazidocarboxylate (2.96 mL, 15.1 mmol) was added dropwise to a stirred mixture of alcohol 109 (1.3 g, 3.76 mmol), Zn(N3)2.2Py (prepared according to the method described by Viaud, M-C; Rollin, P. in Synthesis, 1990,130), triphenylphosphine (3.95 g, 15.1 mmol) and imidazole (1.03 g, 15.1 mmol) in DCM (100 mL) at approximately 0° C. After the addition, the resulting mixture was allowed to warm to ambient temperature and stirred vigorously for 18 h. The reaction mixture was filtered through a short column of silica gel eluted with the appropriate volume of DCM to remove excess salts and polar byproducts. The filtrate was concentrated in vacuo and the crude residue purified by flash chromatography on silica gel (gradient elution; 0%-20% EtOAc/hexanes as eluent) to afford azide 110 as a colorless oil.

Source