1-Methylpyrrole → 3-(1-methyl-1H-pyrrol-2-yl)benzaldehyde

Temperature

-78 °C

EX-602A) To solution of N-methylpyrrole (0.97 mL, 11 mmol) in Et2O (20 mL) was added neat TMEDA (1.5 mL, 10 mmol) and 1.6 M n-BuLi in hexanes (6.3 mL, 10 mmol). The solution was healed to reflux under N2 for 1 h and then cooled to −78° C. A 1.0 M solution of Me3SnCl in THF was added over 15 min, and the resulting solution stirred for 30 min at −78° C. After warming to room temperature, 3-bromo-benzaldehyde (0.70 mL, 6.0 mmol), Pd(PPh3)2Cl2 (0.25 g, 0.35 mmol) and dioxane (10 mL) were added. The slurry was heated to reflux for 18 h. The cooled mixture was poured into a mixture of saturated KF and ethyl acetate and stirred 15 min. The slurry was filtered through celite. The organic layer was separated, washed with brine, dried (MgSO4) and evaporated to an oil. Purification by flash chromatography on silica gel eluting with 5% ethyl acetate in hexane gave 0.45 g (24%) of the desired 3-(1-methyl-1H-pyrrol-2-yl)benzaldehyde product as a yellow oil. MS: m/z=186.2 [M+H]+.

1. temperatureto reflux under N2 for 1 h
2. temperatureAfter warming to room temperature
3. temperatureThe slurry was heated
4. temperatureto reflux for 18 h
5. stirringstirred 15 min
6. filtrationThe slurry was filtered through celite
7. customThe organic layer was separated
8. washwashed with brine
9. dry with materialdried (MgSO4)
10. customevaporated to an oil
11. customPurification by flash chromatography on silica gel eluting with 5% ethyl acetate in hexane

ORD record

ord-2d535f7a287a48ec8e9b957093b361d5

Source dataset

uspto-grants-2002_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06479552B2