synthesis of methyl 2-[2-(alkylimino)-4-oxo-3-phenyl-1,3-thiazolan-5-yliden]acetate derivatives under solvent-free condition

an efficient synthesis of methyl 2-[2-(alkylimino)-4-oxo-3-phenyl-1,3-thiazolan-5-yliden]acetate derivatives via simple three-component reaction and one-pot reactions between isoquinoline, dimethyl acetylenedicarboxylate and n-phenylthiourea under solvent-free conditions without using any additional catalyst, is described. the mild reaction conditions and good yields and exhibit the synthetic advantage of this method. also this method is environmentally friendly. the methods of green chemistry continue to grow in importance. alternative processes help to conserve resources and can even reduce costs. the replacement of convention solvents with water or solvent-free conditions, which is harmless to health and is available in large quantities. the thiazolium rings are key units in agricultural compounds and drugs.