Ammonia → 4-(1-methylpiperidin-4-yloxy)-2-(5-methylthiophen-2-yl)-9,10-dihydro-4H-3,10a-diaza-benzo[f]azulene

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-iodo-4-(1-methylpiperidin-4-yloxy)-9,10-dihydro-4H-3,10a-diaza-benzo[f]azulene (example 2A) (50 mg, 0.12 mmoles) in 1,4-dioxane (2.5 mL) in a screw-capped vial under argon are added 4-methylthiophene-2-boronic acid pinacol ester (40 mg, 0.18 mmole), PdCl2(dppf)2 (6.7 mg, 12 μmole), CsF (36 mg, 0.24 mmoles). The reaction mixture is heated at 100° C. overnight. As the reaction is not completed, CsF (18 mg, 0.12 mmole) and PdCl2(dppf)2 (6.7 mg, 12 μmole) are added and the reaction mixture is heated at 100° C. overnight. Water is added, pH is made alkaline by adding concentrated ammonia solution and 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) as eluent with a gradient from (98:2:0.2) to (96.5:3.5:0.35) followed by a purification on a preparative TLC over silica gel eluting with (9:1:0.1) to give 4-(1-methylpiperidin-4-yloxy)-2-(5-methylthiophen-2-yl)-9,10-dihydro-4H-3,10a-diaza-benzo[f]azulene.

Provenance & Evidence