Ethyl Acetate → (NE,S)-N-[(3-fluoro-2-pyridinyl)methylidene]-2-methylpropane-2-sulfinamide

Participants

Reaction Steps

A mixture of 3-fluoropicolinaldehyde (300 g, 2400 mmol), copper sulfate (572 g, 3600 mmol) and (S)-2-methylpropane-2-sulfinamide (319 g, 2640 mmol) in DCM (3 L) in a 10 L 3-neck round bottom flask was stirred for 3 h at rt. The progress of reaction was monitored by TLC (30% EtOAc in petroleum ether). After completion of reaction, the solid was filtered off and the filtrate was concentrated under vacuum. The residue was purified by column chromatography using silica (60-120 mesh) with 20% EtOAc in n-hexane as eluent to give (S,E)-N-((3-fluoropyridin-2-yl)methylene)-2-methylpropane-2-sulfinamide as a yellow oil. 1H-NMR (400 MHz, CDCl3): δ ppm 8.89 (s, 1H), 8.64 (s, 1H), 7.55 (t, J=8.4 Hz, 1H), 7.46 (d, J=3.6 Hz, 1H), 1.29 (s, 9H). MS (ESI pos. ion) m/z: 155.0 (M−O and t-Bu).

Provenance & Evidence