Cesium fluoride → (Z)-3-Cyclohexyl-2-(5-methanesulfonyl-thiophen-2-yl)-prop-2-en-1-ol

Participants

Reaction Conditions

Reaction Steps

Add 2-bromo-5-methanesulfonyl-thiophene (2.26 g, 9.39 mmol), caesium fluoride ( 2.85 g, 18.78 mmol) and tetrakis-(triphenylphosphin)-palladium(0) (543 mg, 0.47 mmol) to a solution of 3-cyclohexyl-2-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-prop-2-en-1-ol (2.5 g, 9.39 mmol) in dioxane (50 mL). Stir at 80° C. for 24 h, monitor completion of the reaction by LCMS. Treat the reaction mixture with water and extract with dichloromethane. Dry organic layers over sodium sulfate and remove solvents under vacuum to obtain 4.85 g crude product. Purify by siliga gel chromatography, eluting with gradient from 10:0 to 7:3 hexane:ethyl acetate. 690 mg isolated product was (Z)-3-cyclohexyl-2-(5-methanesulfonyl-thiophen-2-yl)-propenal. MS (m/e): 299.0 (M+H). Add a solution of (Z)-3-cyclohexyl-2-(5-methanesulfonyl-thiophen-2-yl)-propenal (690 mg, 2.31 mmol) in methanol (2 mL) to a suspension of NaBH4 in methanol (3 mL) at 0° C. and stir for 1 h, monitor completion of the reaction by LCMS. Dilute reaction mixture with water, extract with ethyl acetate, wash combined organic layers with water and saturated sodium chloride, dry over sodium sulfate and remove solvent under vacuum to obtain 704 mg crude product. MS (m/e): 301.0 (M+H).

Provenance & Evidence