NOVELTY - Chemical synthesis of guaiacol includes at normal temperature, adding toluene and sodium carbonate into a reaction kettle, stirring, adding catechol, steam heating, simultaneously adding dimethyl sulfate into high level groove, heat preserving, dropping dimethyl sulfate, after dropping, heat preserving, adding water into the reaction kettle, cooling, adding sodium hydroxide, obtaining crude methanol solution as by-product, stirring, standing, separating the aqueous layer and organic phase, and introducing the organic phase into desolventizing kettle storage tank.    USE - Chemical synthesis of guaiacol (claimed).    ADVANTAGE - The method has safety, reliability, low cost and low pollution and avoids serious environmental pollution of the prior art.    DETAILED DESCRIPTION - Chemical synthesis of guaiacol comprises providing 450-550 pts. wt. catechol, 450-500 pts. wt. dimethyl sulfate, 420-480 pts. wt. sodium carbonate, 95-115 pts. wt. toluene, 100-120 pts. wt. sodium hydroxide, and 50-100 pts. wt. sulfuric acid, at normal temperature, adding toluene and sodium carbonate into a reaction kettle, stirring, adding catechol, steam heating, simultaneously adding dimethyl sulfate into high level groove, heat preserving, dropping dimethyl sulfate, maintaining the temperature at 95-100 degrees C, after dropping, heat preserving, adding water into the reaction kettle, cooling to 80 degrees C, adding sodium hydroxide, obtaining crude methanol solution as by-product, after heat preservation is ended, stirring, standing for 20 minutes, separating the aqueous layer and organic phase, introducing the aqueous layer into a ground tank, introducing the organic phase into desolventizing kettle storage tank 1, extracting the aqueous layer from the ground tank into an extraction kettle, adding toluene, stirring at 30-40 degrees C, standing and layering, adding aqueous layer into the ground tank, introducing the organic phase into the desolventizing kettle storage tank 1, extracting the aqueous layer from the ground tank into the extraction kettle, adding toluene and sulfuric acid, controlling the temperature at 30-40 degrees C, dropping sulfuric acid into the extraction kettle, continuously stirring, standing and layering, introducing the organic phase into desolventizing kettle storage tank 2, introducing the aqueous layer into a multi-effect evaporator to concentrate, crystallizing to obtain Glauber's salt by-product, condensing the water vapor, taking the organic phase from desolventizing kettle storage tank into the desolventizing kettle, heating at 110 degrees C, condensing the solvent i.e. toluene by a condenser vacuum distilling the crude guaiacol, taking the fraction at more than 120 degrees C and storing into a product tank, returning back the fraction below 120 degrees C to the distillation tower, and placing the product in product tank in a barrel.