1,3,3-Trimethyl-2-methyleneindoline → 8-methacryloxymethyl-6-nitro-1',3',3'-trimethylspiro[2H-1-benzothiopyran-2,2'-indoline]

Participants

Reaction Steps

In 120 ml of 2-butanone were dissolved 14.1 g of 3-methacryloxymethyl-5-nitrothiosalicylaldehyde and 8.7 g of 2-methylene-1,3,3-trimethylindoline, and the solution was heated under reflux for 20 hours in a nitrogen atmosphere. The reaction mixture was concentrated under reduced pressure, and the residue was purified by a silica gel column, giving 15.9 g of 8-methacryloxymethyl-6-nitro-1',3',3'-trimethylspiro[2H-1-benzothiopyran-2,2'-indoline] in the form of pale yellow crystals (yield 73%).

Provenance & Evidence