Study On Novel Green Synthetic Processes Of Several Important Fine Chemicals

With the reckless consumption of fossil resources and energy,the ecological environment is rapidly deteriorating,and humans are facing the most serious resource and environmental crisis ever.To develop green chemistry is the inevitable choice for human existence and social sustainable development.It is very important and meaningful for vigorously promoting green chemistry in the fine-chemical industry.Several important fine chemicals for fields of medicine and coatings were synthesized from the point of view of green chemistry.On the one hand,the process parameters for the preparation of 5-methylfurfural from fructose in solution of H₃PO₃/I^-acid aqueous/toluene were optimized with using cheap H₃PO₃ as co-reductant.The highest 5-methylfurfural molar yield was79.6%under better reaction conditions.The recycle of the aqueous phase was investigated.Furthermore,the yields of 5-methylfurfural from bio-based glucose,inulin,sucrose,and cellulose in the reaction system were examined,and got satisfactory results.Activated carbon supported palladium catalyst was prepared through coating activated carbon with colloidal palladium stabilized by polyvinylpyrrolidone before carbonization.The loading of palladium on activated carbon was 4.86%,and the size of Pd particles is small and uniform（3⁵ nm）.The synthesized catalyst was found to be highly effective to the direct reductive amination of 5-methylfurfural with aniline,and catalyst can be reused at least four timeswithoutsignificantlossofcatalyticactivity.Thesynthesisof N-（5-methylfurfuryl）aniline was a consecutive reaction including dehydration condensation reaction and catalytic hydrogenation reaction.N-（5-methylfurfuryl）aniline molar yield was over 99%under better pressurized conditions.Besides,the scope of the substrate amines was examined,and most of them showed very good results.The toluene solution of fructose-derived 5-methylfurfural from the top organic layer of the reaction system of fructose to5-methylfurfural was used as raw material for pressurized reductive amination with aniline aftersimplepurification.Thus,withthistwo-stepapproach,renewable N-（5-methylfurfuryl）aniline was produced from fructose.We deduced the plausible reaction pathway for production of 5-methylfurfural from fructose and the collaborative mechanism of solution of H₃PO₃/I^-acid aqueous/toluene.And the reaction mechanism of direct reductive amination of 5-methylfurfural catalyzed by activated carbon supported palladium was also discussed.On the other hand,we provided a solvent-free method to modify allyl methacrylate（AMA）with 1,1,1,3,5,5,5-heptamethyltrisiloxane（MD^HM）through atomic economic hydrosilylation reaction catalyzed by Speier’s catalyst.We also studied the application of MD^HM modified AMA in waterborne self-matting styrene-acrylic emulsions.It turned out that MD^HM modified AMA contains unsaturated isopropenyl catalyzed synthesized by catalyst and using 2,6-di-tert-butyl-4-methylphenol as polymerization inhibitor without any other solvent.The conversion of MD^HM and AMA reach 88%and 92%respectively under optimized conditions.As for the formulas used in this paper,the surface gloss of emulsion coating film with MD^HM modified AMA comparatively decreased 71%with that without modified AMA and considered as semi-gloss,and the water contact angle of film with MD^HM modified AMA increased 63%compared with blank controller.These results were associated with the structure of the silicone chain segments exposing to the air-film interface.