Preparation method of green N-methyl amide compound

The invention discloses a preparation method of a green N-methyl amide compound. An LED lamp is used as a light source to provide energy, economical and easily available tertiary amide is used as a reaction substrate, copper chloride is used as a catalyst, hydrochloric acid which can be purchased in the market is used as an additive, and acetone is used as a solvent. Compared with the prior art, the method disclosed by the invention has the following advantages: a green, mild and environment-friendly visible light catalysis reaction mode is adopted; the reaction system is simple, the substrate range is wide, and aromatic and aliphatic amides are suitable for the method; the reaction yield is high; operation is simple, and raw materials are cheap and easy to obtain.