p-Toluenesulfonic acid monohydrate → 5-isocyano-2,3-dihydroinden-1-one O-tert-butyldimethylsilyl oxime

Participants

Reaction Steps

5-isocyano-2,3-dihydroinden-1-one (6) (3.00 g, 19.1 mmol) was combined with 1.4 eq. of O-(tert-butyldimethylsilyl)hydroxylamine (3.94 g, 26.7 mmol) and TsOH-H2O (0.363 g, 1.91 mmol) in 100 mL CHCl3 and heated to reflux overnight. TLC showed a small amount of remaining starting material and two non-polar spots corresponding to the oxime isomers. The reaction mixture was filtered and concentrated to a brown semi-solid, then purified immediately by loading onto a silica column with DCM and eluting with 1% MeOH/DCM to give 4.1 g (75%) of 5-isocyano-2,3-dihydroinden-1-one O-tert-butyldimethylsilyl oxime (7).

Provenance & Evidence