تفاعل #1763126

معادلة التفاعل

HCl

KOH

3-methyl-5-pyridylboronic acid

water

cesium carbonate

3-methylpyrazole

NaHMDS

→

title compound ( 5-2 )

5′-methyl-6-(3-methyl-1H-pyrazol-1-yl)-3,3′-bipyridine-5-carboxylic acid

المذيبات

THF

MeOH

dimethylformamide

MeOH

dioxane

diethylether

ظروف التفاعل

المعالجة

1. 1
   أخرىThe system was partitioned between water and EtOAc
2. 2
   تجفيفdried over magnesium sulfate
3. 3
   ترشيحFiltration and concentration
4. 4
   أخرىyielded a brown oil which
5. 5
   أخرىupon purification via normal phase chromatography (0→100% EtOAc in Hx)
6. 6
   أخرىafforded a brown semi-solid which
7. 7
   أخرىto yield a dark tan powder
8. 8
   درجة الحرارةthe system was heated to 125° C. for 20 minutes in the microwave reactor
9. 9
   أخرىThe reaction contents
10. 10
    أخرىwere partitioned between water and EtOAc
11. 11
    أخرىfollowed by purification via normal phase chromatography (20→100% EtOAc in Hx)
12. 12
    أخرىto yield a clear oil
13. 13
    workup.STIRRINGstirred at 135° C. for 10 minutes in a microwave reactor
14. 14
    أخرىthe solvents were azeotroped off with toluene

الإجراء التجريبي

To a solution of methyl 2-chloro-5-iodonicotonate (5-1, 10.85 g, 36.5 mmol) in dimethylformamide (150 mL) at 25° C. was added 3-methyl-5-pyridylboronic acid (5.0 g, 36.5 mmol), PdCl2dppf (2.67 g, 3.65 mmol) followed by cesium carbonate (41.6 g, 128 mmol) and water (6.57 mL, 365 mmol) and the system was stirred for 4 h at 25° C. The system was partitioned between water and EtOAc, and dried over magnesium sulfate. Filtration and concentration yielded a brown oil which upon purification via normal phase chromatography (0→100% EtOAc in Hx) afforded a brown semi-solid which was then tritirated with MeOH and diethylether to yield a dark tan powder. To this tan powder (0.5 g, 1.9 mmol) in dioxane (13 mL) was added 3-methylpyrazole (0.47 g, 5.7 mmol) and NaHMDS (1.9 mL, 3.81 mmol) and the system was heated to 125° C. for 20 minutes in the microwave reactor. The reaction contents were partitioned between water and EtOAc followed by purification via normal phase chromatography (20→100% EtOAc in Hx) to yield a clear oil. To this clear oil (0.31 g, 1.0 mmol) in THF (2.5 mL) and MeOH (2.5 mL) was added KOH (2.0 mL, 2.0 mmol) and stirred at 135° C. for 10 minutes in a microwave reactor. The system was then acidified using 6 N HCl to a pH of 2.0 and the solvents were azeotroped off with toluene to afford the title compound (5-2) as a bone powder. ESI+MS [M+H]+ C16H14N4O2=295.1.

المصدر