Cesium carbonate → {4-[1-methyl-4-(1-methylpiperidin-4-yloxy)-9,10-dihydro-4H-3,10a-diaza-benzo[f]azulen-2-yl]-phenyl}-carbamic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

In a screw-capped vial are added 2-(4-bromophenyl)-1-methyl-4-(1-methylpiperidin-4-yloxy)-9,10-dihydro-4H-3,10a-diaza-benzo[f]azulene (example 122A) (250 mg, 0.54 mmole), Pd(dba)2 (25 mg, 27 μmole), Xantphos (31 mg, 54 μmole), Cs2CO3 (704 mg, 2.16 mmoles), 1,4-dioxane (3.4 mL) and tert-butyl carbamate (316 mg, 2.7 mmoles). The flask is evacuated and filled with argon. The reaction mixture is heated at 110° C. for 4 hours. Water is added and pH adjusted to 10 with a few drops of 1N NaOH. The aqueous phase is extracted three times with CH2Cl2. The organic phase is dried over magnesium sulphate, filtered and the solvent is removed under reduced pressure. The residue is purified by silica gel chromatography using (CH2Cl2:MeOH:NH4OH) with a gradient from (100:0:0) to (95:5:0.5) to give {4-[1-methyl-4-(1-methylpiperidin-4-yloxy)-9,10-dihydro-4H-3,10a-diaza-benzo[f]azulen-2-yl]-phenyl}-carbamic acid tert-butyl ester melting at 194° C.

Provenance & Evidence