Piperidine → 3-((3-((E)-2-(pyridin-4-yl)vinyl)-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-indazol-5-yl)methylene)indolin-2-one

Participants

Reaction Conditions

Reaction Steps

A solution of piperidine (0.2M in EtOH, 0.10 mL, 0.02 mmol) was added to a suspension of oxindole (16.5 mg, 0.12 mmol) and (E)-3-(2-(pyridin-4-yl)vinyl)-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-indazole-5-carbaldehyde (42.5 mg, 0.11 mmol) in EtOH (4 mL). The reaction was then heated to 75° C. for 15 hrs. The solvent was evaporated in vacuo. MeOH was added and the resulting suspension was sonicated, but the solution was still cloudy even after EtOAc was added. The solid was removed by filtration and the solvent evaporated in vacuo. Chromatography (5 g silica SPE tube, Silicycle, 2% MeOH in CH2Cl2) gave a yellow solid (35 mg, 64%, 55:45 mixture of E/Z isomers). 1H NMR (400 MHz, CDCl3 plus a drop of CD3OD) δ 9.77 (s, 0.45H), 8.63 (m, 1.9H), 8.42 (s, 0.55H), 8.18 (s, 0.45H), 8.14 (dd, J=8.8, 1.2 Hz, 0.45H), 8.00 (s, 1H), 7.83-7.42 (m, 7H), 7.26 (t, J=7.6 Hz, 1H), 7.09 (t, J=7.6 Hz, 0.45H), 6.94-6.88 (m, 1.6H), 5.80 (s, 0.55H), 5.77 (s, 0.45H), 3.64 (m, 2H), 0.95 (m, 2H), −0.02 (s, 5H), −0.03 (s, 4H).

Provenance & Evidence