[C:1]([C:4]1[CH:5]=[C:6]([N:16]2[CH2:21][CH2:20][N:19]([C:22]([O:24][C:25]([CH3:28])([CH3:27])[CH3:26])=[O:23])[CH2:18][CH2:17]2)[C:7]2[C:12]([CH:13]=1)=[CH:11][CH:10]=[C:9]([O:14][CH3:15])[CH:8]=2)(=[O:3])[CH3:2]>COC(OC)N(C)C>[CH3:6][N:16]([CH3:21])/[CH:17]=[CH:2]/[C:1]([C:4]1[CH:5]=[C:6]([N:16]2[CH2:21][CH2:20][N:19]([C:22]([O:24][C:25]([CH3:28])([CH3:27])[CH3:26])=[O:23])[CH2:18][CH2:17]2)[C:7]2[C:12]([CH:13]=1)=[CH:11][CH:10]=[C:9]([O:14][CH3:15])[CH:8]=2)=[O:3]tert-butyl 4-(3-acetyl-7-methoxynaphthalen-1-yl)piperazine-1-carboxylate (107) (1.5 g) and N,N-dimethylformamide dimethylacetal were charged in a flask and heated at 100° C. for 36 hours. More N,N-dimethylformamide dimethylacetal (10 ml) was added to the reaction, the temperature was raised to 120° C. and the reaction was allowed to proceed overnight. The reaction was cooled and poured onto water. The solid was extracted with ethyl acetate (2×100 ml), the organics combined, washed with water (1×100 ml) and brine (1×100 ml), dried over sodium sulfate and concentrated. Column chromatography (100% ethyl acetate) gave (E)-tert-butyl 4-(3-(3-(dimethylamino)acryloyl)-7-methoxynaphthalen-1-yl)piperazine-1-carboxylate (108) as a light yellow foam (1.59 g) LCMS (m/z): 440 [M+H].
Loading…