Cyclopropyl methyl ketone → (NE)-N-(1-cyclopropylethylidene)-2-methylpropane-2-sulfinamide
Reaction equation
[CH:1]1([C:4](=O)[CH3:5])[CH2:3][CH2:2]1.[CH3:7][C:8]([S:11]([NH2:13])=[O:12])([CH3:10])[CH3:9]>C1COCC1>[CH:1]1(/[C:4](=[N:13]/[S:11]([C:8]([CH3:10])([CH3:9])[CH3:7])=[O:12])/[CH3:5])[CH2:3][CH2:2]1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
A mixture of 1-cyclopropylethanone (1 g, 12 mmol), 2-methylpropane-2-sulfinamide (1.7 g, 14 mmol), Ti(OEt)4 (5.5 g, 24 mmol) in 10 mL of THF was heated at reflux with stirring overnight. The mixture was cooled to room temperature, solvent was removed under reduced pressure and the crude residue was purified by column chromatography (silica gel, 200-300 mesh, petroleum ether and ethyl acetate (3:1, v/v) to give (E)-N-(1-cyclopropylethylidene)-2-methylpropane-2-sulfinamide (0.6 g, 27%) as clear oil. MS: (M+H)+=188.2; 1H NMR (300 MHz, CDCl3): δ 2.36 (s, 3H), 1.69 (m, 1H), 1.18 (s, 9H), 1.07-0.89 (m, 4H).