Reaction #157940

Reaction equation

2-chloro-3,5-dimethylpyrazine

sodium carbonate

1-naphthylboronic acid

→

2-(1-naphthyl)-3,5-dimethylpyrazine

Yield 59.0%

Solvents

water

acetonitrile

water

Conditions

Workup

1. 1
   OtherFirst, into a recovery flask equipped with a reflux pipe
2. 2
   OtherThis reaction container was subjected to irradiation with microwaves (2.45 GHz, 100 W) for 10 minutes
3. 3
   Temperaturewhereby heating
4. 4
   Extractionan organic layer was extracted with dichloromethane
5. 5
   WashThe obtained organic layer was washed with water
6. 6
   Dryingdried with magnesium sulfate
7. 7
   FiltrationAfter the drying, the solution was filtered
8. 8
   workup.DISTILLATIONThe solvent of this solution was distilled off
9. 9
   Otherthe obtained residue was purified by silica gel column chromatography
10. 10
    Otherto be produced
11. 11
    Otherwas obtained
12. 12
    OtherNote that the irradiation with microwaves
13. 13
    Othera microwaves synthesis system (Discover, produced by CEM Corporation)
14. 14
    OtherThe synthesis scheme of Step 1

Procedure

First, into a recovery flask equipped with a reflux pipe were put 2.05 g of 2-chloro-3,5-dimethylpyrazine, 2.48 g of 1-naphthylboronic acid, 1.53 g of sodium carbonate, 0.066 g of bis(triphenylphosphine)palladium(II)dichloride (abbreviation: Pd(PPh3)2Cl2), 15 mL of water, and 15 mL of acetonitrile, and the air in the flask was replaced with argon. This reaction container was subjected to irradiation with microwaves (2.45 GHz, 100 W) for 10 minutes, whereby heating was performed. After that, water was added to this solution, and an organic layer was extracted with dichloromethane. The obtained organic layer was washed with water and dried with magnesium sulfate. After the drying, the solution was filtered. The solvent of this solution was distilled off, and then the obtained residue was purified by silica gel column chromatography using dichloromethane as a developing solvent. Accordingly, Hdm1npr (a light orange powder, 59% yield), which was the substance to be produced, was obtained. Note that the irradiation with microwaves was performed using a microwaves synthesis system (Discover, produced by CEM Corporation). The synthesis scheme of Step 1 is shown in (a-1) below.

Source