1,4-Dibromobenzene → methyl (S)-3-(4-bromophenyl)-2-hydroxypropionate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

72 ml (0.122 mol, 2.5 eq) of tert-butyllithium (1.7M/pentane) are added slowly using a needle to a suspension of 35 g (0.148 mol, 3 eq) of 1,4-dibromobenzene in 100 ml of tert-butyl methyl ether at −30° C. The mixture is stirred at −30° C. for 10 min and then 5.3 g (0.059 mol) of copper(I) cyanide are introduced into the above solution. The reaction mixture is stirred at −30° C. for 20 min. A solution of 5 g (0.049 mol) of methyl (S)-glycidate in 10 ml of tert-butyl methyl ether is added while keeping the temperature below −20° C. The mixture is stirred at −30° C. for 20 min and then the reaction is halted by the addition of a saturated ammonium chloride solution. The mixture is extracted with 3×300 ml of ethyl acetate. The organic phases are combined and dried over sodium sulfate. The solvents are evaporated and then the residue is chromatographed on silica gel (heptane 100% up to heptane/ethyl acetate 60/40). 7.2 g of methyl (S)-3-(4-bromophenyl)-2-hydroxypropionate are obtained in the form of a solid. Yield=56%.

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