Thiophene → Ethyl 4-[(5,5-dimethyl-8-(2-thienyl)-5,6-dihydronaphthalen-2-yl)azo]benzoate

To a cold solution (-78° C.) of thiophene (0.07 ml, 0.75 mmol) in 1.5 ml of TBF was added t-BuLi (0.457 ml, 0.75 mmol, 1.7 M in pentane) and stirred for 2 h. To this solution, ZnCl2 (168 mg, 1.2 mmol) in 1.5 ml of THF was added. The resulting solution was warmed to room temperature, stirred for 1 h and was added (via cannula) to a solution of ethyl 4-[(5,6-dihydro-5,5-dimethyl-8-trifluoromethylsulfonyloxy-naphthalen-2-yl)azo]benzoate (Compound D11, 150 mg, 0.30 mmol) and tetrakis(triphenylphosphine)palladium(O) (10.6 mg) in 2.5 ml of THF. The resulting mixture was heated at 50° C. for 2.5 h. The reaction was diluted with sat. aqueous NH4Cl and extracted with ethyl acetate. The combined organic layer was dried over Na2SO4 and concentrated to an oil. The crude product was purified by flash chromatography (silica, ethyl acetate: hexane 5:95) to afford the title compound as a red foam.

1. stirringstirred for 1 h
2. temperatureThe resulting mixture was heated at 50° C. for 2.5 h
3. extractionextracted with ethyl acetate
4. dry with materialThe combined organic layer was dried over Na2SO4
5. concentrationconcentrated to an oil
6. customThe crude product was purified by flash chromatography (silica, ethyl acetate: hexane 5:95)

ORD-Eintrag

ord-d027a9a430ec440a95a5cb28e4f80a03

Quelldatensatz

uspto-grants-1999_12

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05998655