C([Li])CCC.Br[C:7]1[CH:8]=[C:9]2[C:14](=[CH:15][CH:16]=1)[CH:13]=[C:12]([C:17]1[N:21]=[C:20]([CH3:22])[O:19][N:18]=1)[CH:11]=[CH:10]2.C[O:24][B:25](OC)[O:26]C.Cl>O1CCCC1>[CH3:22][C:20]1[O:19][N:18]=[C:17]([C:12]2[CH:13]=[C:14]3[C:9](=[CH:10][CH:11]=2)[CH:8]=[C:7]([B:25]([OH:26])[OH:24])[CH:16]=[CH:15]3)[N:21]=14.76 ml n-butyllithium solution (1.6 M in hexane) are added dropwise to 1.00 g 3-(6-bromo-naphthalen-2-yl)-5-methyl-[1,2,4]oxadiazole in 15 ml of tetrahydrofuran at −78° C. The reaction mixture is stirred for another hour at −78° C., then 1.94 ml trimethylborate are added dropwise. Then the reaction mixture is left to heat up to ambient temperature and stirred overnight at this temperature. Then 9 ml 1 N hydrochloric acid are added while cooling with an ice bath. After 10 minutes at ambient temperature the tetrahydrofuran is distilled off in vacuo using the rotary evaporator and the flask residue is extracted with ethyl acetate. The combined organic extracts are dried on magnesium sulphate and evaporated down. The crude product is stirred with diisopropylether, suction filtered and dried.
読み込み中…
