Sodium Carbonate → tert-butyl 6-cyclohexyl-5-(2-formylphenyl)-4-(2-methoxy-2-oxoethyl)-4H-thieno[3,2-b]pyrrole-2-carboxylate

Participants

Reaction Steps

tert-Butyl 5-bromo-6-cyclohexyl-4-(2-methoxy-2-oxoethyl)-4H-thieno[3,2-b]pyrrole-2-carboxylate (1 eq., from Step 3) and 2-formyl-phenylboronic acid (1.5 eq.) were dissolved in dioxane (0.1 M) and treated with 2 M Na2CO3 solution (2 eq.). The solution was degassed by bubbling argon through it and Pd(PPh3)2Cl2 (0.1 eq.) was added. The reaction mixture was heated to reflux for 20 min then allowed to cool down to RT, diluted with EtOAc and washed with 1 N hydrochloric acid and with brine. The organic layer was dried over sodium sulfate, evaporated in vacuo and the residue purified by chromatography (PE:EtOAc, 9:1) to afford the pure title compound (68%) as a solid. 1H-NMR (400 MHz, DMSO-d6, 300 K, δ) 9.70 (s, 1H), 7.96 (dd, J 7.7, 1.3, 1H), 7.91 (s, 1H), 7.84 (dt, J 7.6, 1.5, 1H), 7.80 (t, J 7.7, 1H), 7.47 (d, J 7.6, 1H), 4.93 (d, J 18.2, 1H), 4.76 (d, J 18.2, 1H), 3.48 (s, 3H), 2.15-2.08 (m, 1H), 1.73-1.02 (m, 10H), 1.52 (s, 9H). MS (ES+) m/z: 482 [M+H]+.

Provenance & Evidence