Reacción #85548

Ecuación de reacción

NH4Cl

n-BuLi

3-bromopyridine

2-benzothiazol-2-yl-3,3-bismethylsulfanylacrylonitrile

3-pyridinyl lithium

→

desired product

Rendimiento 65.0%

4-Benzothiazol-2-yl-5-pyridin-3-yl-1H-pyrazol-3-ylamine

Rendimiento 65.0%

Disolventes

cyclohexane

ether

THF

THF

Condiciones de reacción

Tratamiento posterior

1. 1
   Otrowas prepared
2. 2
   Temperaturaslowly warmed up to room temperature
3. 3
   workup.STIRRINGstirred at that temperature for 2 hours
4. 4
   OtroUpon completion of the reaction
5. 5
   ExtracciónThe aqueous phase was extracted with ethyl acetate
6. 6
   LavadoThe organic phase was washed with brine
7. 7
   Secadodried over magnesium sulfate
8. 8
   Filtraciónfiltered
9. 9
   Otroevaporated
10. 10
    OtroThe crude material was then purified by flash chromatography
11. 11
    Lavadoeluting with CH2Cl2

Procedimiento

A yellow suspension of 3-pyridinyl lithium in THF was prepared according to the literature (Cama, L. D.; Wildonger, K. J.; Guthikonda, R.; Ratcliffe, R. W.; Christensen, B. G. Tetrahedron (1983), 39, 2531) by adding n-BuLi (0.25 mL of a 2 M solution in cyclohexane, 0.5 mmol) to a solution of 3-bromopyridine (87 mg, 0.5 mmol) in anhydrous ether (3 mL) at −78° C. To this slurry was rapidly added 2-benzothiazol-2-yl-3,3-bismethylsulfanylacrylonitrile (140 mg, 0.5 mmol) in anhydrous THF (5 mL) under argon. The resulting mixture was stirred at −78° C. for 1 hour, and then slowly warmed up to room temperature and stirred at that temperature for 2 hours. Upon completion of the reaction, the mixture was poured into a saturated NH4Cl aqueous solution. The aqueous phase was extracted with ethyl acetate. The organic phase was washed with brine, dried over magnesium sulfate, filtered and evaporated. The crude material was then purified by flash chromatography eluting with CH2Cl2:MeOH=1:0-19:1 to yield 100 mg (65%) of the desired product as a brown oil. MS (m/z, ES+): 310 (M+1, 25%), 263 (M−46, 100%).

Fuente