反应详情

Into a 50-mL three-neck flask were put 1.2 g (3.3 mmol) of 2-(3-bromophenyl)-1-phenyl-1H-benzimidazole, 0.8 g (3.3 mmol) of dibenzothiophene-4-boronic acid, and 50 mg (0.2 mmol) of tri(ortho-tolyl)phosphine. The air in the flask was replaced with nitrogen. To this mixture were added 3.3 mL of a 2.0 mmol/L aqueous solution of potassium carbonate, 12 mL of toluene, and 4 mL of ethanol. Under reduced pressure, this mixture was stirred to be degassed. Then, 7.4 mg (33 μmol) of palladium(II) acetate was added to this mixture, and the mixture was stirred at 80° C. for 6 hours under a nitrogen stream. After a predetermined time, the aqueous layer of the obtained mixture was subjected to extraction with toluene. The solution of the obtained extract combined with the organic layer was washed with saturated brine, and then the organic layer was dried over magnesium sulfate. This mixture was separated by gravity filtration, and the filtrate was concentrated to give an oily substance. This oily substance was purified by silica gel column chromatography. The silica gel column chromatography was carried out using toluene as a developing solvent. The obtained fraction was concentrated to give an oily substance. This oily substance was purified by high performance liquid chromatography. The high performance liquid chromatography was performed using chloroform as a developing solvent. The obtained fraction was concentrated to give an oily substance. This oily substance was recrystallized from a mixed solvent of toluene and hexane, so that the substance which was the object of the synthesis was obtained as 0.8 g of a pale yellow powder in 51% yield. The synthesis scheme is illustrated in the following formula.

1. customInto a 50-mL three-neck flask were put
2. customto be degassed
3. stirringthe mixture was stirred at 80° C. for 6 hours under a nitrogen stream
4. extractionAfter a predetermined time, the aqueous layer of the obtained mixture was subjected to extraction with toluene
5. extractionThe solution of the obtained extract
6. washwas washed with saturated brine
7. dry with materialthe organic layer was dried over magnesium sulfate
8. customThis mixture was separated by gravity filtration
9. concentrationthe filtrate was concentrated
10. customto give an oily substance
11. customThis oily substance was purified by silica gel column chromatography
12. concentrationThe obtained fraction was concentrated
13. customto give an oily substance
14. customThis oily substance was purified by high performance liquid chromatography
15. concentrationThe obtained fraction was concentrated
16. customto give an oily substance
17. customThis oily substance was recrystallized from a mixed solvent of toluene and hexane, so that the substance which