Tetrahydrofuran → HCID 18669682, compound

Temperature

-55 °C

Chloromethyltrimethylsilane (1.875 g, 15.37 mmol) in dry THF (45 ml) at −78° C. was treated with sec-butyllithium (13.0 ml of 1.3 M solution in cyclohexane, 16.88 mmol) followed by TMEDA (2.4 ml, 16.1 mmol). The mixture was stirred for 40 min, then warmed to −55° C. 4′-Bromo-4-cyclopentoxy-3-methoxybenzophenone (4.0 g, 10.6 mmol) in THF (20 ml) was added and the mixture stirred at −40° C. for 0.5 h. It was then warmed to room temperature gradually and stirred for an additional 18 h. The reaction was quenched with aqueous ammonium chloride solution and the resultant mixture extracted three times with ethyl acetate. The combined organic extract was washed with water then brine, dried (sodium sulfate) and evaporated. The residue was purified by flash chromatography (silica gel, 4% ethyl acetate/96% hexane). The resulting yellow oil was stirred in 50 ml of 20% trifluoroacetic acid in dichlomethane for one hour then washed three times with water, once with dilute sodium bicarbonate, twice with water, once with brine and dried (sodium sulfate). The solvent was evaporated to provide the title compound as a yellow oil (1.757 g, 42.5%). 1H-NMR (400 MHz, CDCl3): δ 9.87 (s, 1H), 7.49 (d, 2H, J=8.4), 7.07 (d, 2H, J=8.4), 6.87 (d, 1H, J=8.2), 6.70 (dd, 1H, J=2.2, J=8.3), 6.68 (d, 1H, J=2.2).

1. stirringthe mixture stirred at −40° C. for 0.5 h
2. temperatureIt was then warmed to room temperature gradually
3. stirringstirred for an additional 18 h
4. customThe reaction was quenched with aqueous ammonium chloride solution
5. extractionthe resultant mixture extracted three times with ethyl acetate
6. extractionThe combined organic extract
7. washwas washed with water
8. dry with materialbrine, dried (sodium sulfate)
9. customevaporated
10. customThe residue was purified by flash chromatography (silica gel, 4% ethyl acetate/96% hexane)
11. stirringThe resulting yellow oil was stirred in 50 ml of 20% trifluoroacetic acid in dichlomethane for one hour
12. washthen washed three times with water
13. dry with materialonce with dilute sodium bicarbonate, twice with water, once with brine and dried (sodium sulfate)
14. customThe solvent was evaporated

ORD record

ord-2ad0775fb2cf4c76ad77dab30dc2a78e

Source dataset

uspto-grants-2003_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06518306B1