Reaction Steps
A solution mixture of 1,4-dimethylquinolinium iodide (0.14 g, 0.5 mmol), 3b (0.13 g, 0.6 mmol) and piperidine (0.1 mL) in ethanol (40 mL) was heated to reflux overnight. After cooling down to room temperature, the organic solvent was removed. The residue was purified by precipitation from methanol and ethyl acetate to afford Me-SLM (0.14 g) in 62% yield. 1H NMR (400 MHz, DMSO-d6) δ 9.27 (d, J=6.4 Hz, 1H), 9.12 (d, J=8.4 Hz, 1H), 8.86 (s, 1H), 8.49 (d, J=6.4 Hz, 1H), 8.45-8.23 (m, 5H), 8.15 (d, J=8.8 Hz, 1H), 8.06 (t, J=7.6 Hz, 1H), 7.75 (d, J=8.4 Hz, 1H), 7.66 (d, J=8.0 Hz, 1H), 7.55 (t, J=7.6 Hz, 1H), 7.32 (t, J=7.6 Hz, 1H), 4.51 (s, 3H), 3.95 (s, 3H). 13C NMR (400 MHz, DMSO-d6) δ 152.9, 147.3, 144.8, 142.2, 141.2, 138.7, 134.8, 128.8, 127.4, 126.6, 126.4, 126.3, 126.0, 122.6, 122.0, 121.8, 120.4, 119.7, 119.1, 116.0, 115.0, 109.8, 109.7, 44.3, 29.3. HRMS (MALDI-TOF) m/z Calcd for C25H21N2 349.1699. Found 349.1694 [M]+.