Potassium Acetate → 4-Chloro-2-(1-oxo-3,4,6,7,8,9-hexahydropyrido[3,4-b]indolizin-2(1H)-yl)nicotinaldehyde

Participants

Reaction Conditions

Reaction Steps

A 250-mL single-neck round-bottomed flask equipped with a magnetic stirrer and reflux condenser was charged with 1,4-dioxane (50 mL), 2-bromo-4-chloronicotin-aldehyde 103a (1.4 g, 6.4 mmol), 3,4,6,7,8,9-hexahydropyrido[3,4-b]indolizin-1(2H)-one 112d (0.6 g, 3.2 mmol), Pd2(dba)3 (293 mg, 0.32 mmol), XantPhos (370 mg, 0.64 mmol), and potassium acetate (627 mg, 6.4 mmol). After three cycles of vacuum/argon flush, the mixture was heated at 80° C. overnight. After this time the reaction was cooled to room temperature. It was then filtered and the filtrate was evaporated in vacuo. The residue was purified by silica gel column chromatography eluting with CH2Cl2/CH3OH (20:1, UV) to afford 147a (528 mg, 50%) as a yellow solid. MS: [M+H]+ 330. 1H NMR (500 MHz, CDCl3) δ 10.09 (s, 1H), 8.37 (d, J=5.5, 1H), 7.16 (d, J=5.5, 1H), 6.25 (s, 1H), 4.29-4.32 (m, 2H), 3.83-3.86 (m, 2H), 2.96-2.99 (m, 2H), 2.77-2.78 (m, 2H), 2.00-2.07 (m, 2H), 1.83-1.85 (m, 2H)

Provenance & Evidence