2,4-Dichloro-1-iodobenzene → [1-(2,4-Dichlorophenyl)piperidin-4-yl]methanol

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

**_Procedure:_** To a flask was added 1,3-Dichloro-4-iodobenzene (5.89 mL, 43.41 mmol), piperidin-4-ylmethanol (5 g, 43.41 mmol), cesium carbonate (28.3 g, 86.83 mmol), 18-Crown-6 (1.377 g, 5.21 mmol), rac-2,2'-Bis(diphenylphosphino)-1,1'-binaphthyl (0.811 g, 1.30 mmol), and toluene (50 mL). The mixture was stirred under nitrogen and Tris(dibenzylideneacetone)dipalladium(0) (0.398 g, 0.43 mmol) was added in one portion. The resultant yellow mixture was heated with oil bath temperature set at 125°C for 3 hours. LCMS shows desired product as well as other impurities. The reaction was cooled to room temperature. Ethyl acetate (2 x 200 mL) was added and the resultant mixture was extracted with saturated aqueous sodium chloride (200 mL). The organics were collected and dried over sodium sulfate. Ethyl acetate (100 mL) and hexanes (100 mL) were added to the crude and insoluble material filltered off. The filtrate was concentrated and chromatographed on silica gel (divided into 3 40 gram silica gel columns). The columns were eluted with hexanes up to ethyl acetate:hexanes (up to 100%). The desired product eluted between 40-60% ethyl acetate:hexanes. Clean fractions were combined from all columns and concentrated to give EN01972-36-1 (2.47 g, 21.87% yield) as an orange oil.

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