3-methylthio-3-alkenyl indolone derivative and preparation method thereof

The invention relates to the technical field of organic chemical synthesis, and particularly discloses a 3-methylthio-3-alkenyl indolone derivative and a preparation method thereof. The invention relates to a 3-methylthio-3-alkenyl indolone derivative, which is characterized in that the molecular structural formula is as follows: # imgabs0 #, in the formula, R1 is one of acetyl and aryl acetyl with 7-13 carbon atoms; r2 is one of methyl, ethyl, n-propyl, isopropyl, butyl, isobutyl, tertiary butyl, allyl, benzyl, phenyl and acetyl; and R3 is one of hydrogen, fluorine, chlorine, bromine, iodine, methyl, trifluoromethyl, tertiary butyl, phenyl, methoxyl, cyano and acetoxy. The synthesis method disclosed by the invention has the advantages of high atom economy, high selectivity, high yield, unique reaction route, simple synthesis steps, good functional group tolerance and the like, and has a wide application prospect. Ketene dithioacetal is used as a methylthio reagent, and the application is carbon-sulfur bond i