Dimethylformamide → 2-Bromo-9,9-dimethoxyethylfluorene

Temperature

45 °C

To a solution of 2-bromofluorene (2.0 g, 8.2 mmol) in dimethylformamide (dry, 30 ml) was added potassium t-butoxide (2.74 g, 24.4 mmol), giving a deep orange in color. The mixture was stirred at 45° C. for 20 min and added 2-bromoethylmethyl ether (3.5 g, 2.5 mmol) dropwise. Stirring was continued at the same temperature for overnight to give an orange solution. Another portion of 2-bromoethylmethyl ether (1.4 g, 1.0 mmol) was added and the mixture stirred at 80° C. for 4 h. It was diluted with water (100 ml). The products extracted with ethylacetate (20 ml) and washed with water. Organic layer was dried over magnesium sulfate and concentrated in vacuuo to afford the crude product. It was purified by preparative thin layer chromatography (silica gel, Rf=0.3 using hexane-EtOAc/3:2 as eluent) to give 2-bromo-9,9-dimethoxyethylfluorene (1.5 g).

1. customgiving a deep orange in color
2. stirringStirring
3. waitwas continued at the same temperature for overnight
4. customto give an orange solution
5. stirringthe mixture stirred at 80° C. for 4 h
6. extractionThe products extracted with ethylacetate (20 ml)
7. washwashed with water
8. dry with materialOrganic layer was dried over magnesium sulfate
9. concentrationconcentrated in vacuuo
10. customto afford the crude product
11. customIt was purified by preparative thin layer chromatography (silica gel, Rf=0.3 using hexane-EtOAc/3:2 as eluent)

ORD record

ord-dc989689314d4eefbdcd9bd4ab551516

Source dataset

uspto-grants-2006_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07132572B2