Study On The Synthesis Process Of Exaltolide

Cyclopentadecanolide is an important macrocyclic musk, which does not only tastemusk, but also held rhyme. With thick and exquisite fragrance, though expensive, it iswidely used in perfumes, fragrances, cosmetics, food, medicine and other fields.The process using dodecanedioic acid as starting material to synthesizecyclopentadecanolide is studied in this paper. Dimethyl dodecanedioate was obtainedthrough the esterfication of dodecanedioic acid.15-Hydroxy-12-oxopentadecanoic acidwas synthesized through the Claisen condensation of dodecanedioic acid and thedecarbonation of alkali metal hydroxide.15-Hydroxypentadecanoic acid was preparedfrom the clemmensen reaction of15-Hydroxy-12-oxopentadecanoic acid, with theamalgam zinc as catalyst. Cyclopentadecanolid was obtained through the cyclizationreaction of15-Hydroxypentadecanoic acid; with the4-(dimethylamino)pyridine,4-(dimethylamino)pyridine hydrochloride and dicyclohexyl carbodiimide as catalyst.By experiment, on which each step response optimization experiment, find a optimumprocess conditions and each step reaction yield is good.⑴15-Hydroxy-12-oxopentadecanoic acid was synthesized through the Claisencondensation of dodecanedioic acid and the decarbonation of alkali metal hydroxide.The best condition of experiment obtained through single factor and orthogonalexperiment is: the mole ratio of dimethyl dodecanedioate and γ-butyrolactone is1:1; theratio of dimethyl dodecanedioate and methanol is1g:1ml; the Sodium hydroxideconcentration is5%, product yield was68%.⑵15-Hydroxypentadecanoic acid was prepared from the clemmensen reaction of15-Hydroxy-12-oxopentadecanoic acid, with the amalgam zinc as catalyst. The bestcondition of experiment obtained through single factor and orthogonal experiment is:the mole ratio of raw material and mercuric chloride is7:1(the mole ratio of mercuricchloride and zinc is1:42); the ratio of raw material and strong hydrochloric acid is3g:25ml; the reaction temperature is120℃, the product yield was81%⑶Cyclopentadecanolid was obtained through the cyclization reaction of15-Hydroxypentadecanoic acid; with the4-(dimethylamino)pyridine,4-(dimethylamino)pyridine hydrochloride and dicyclohexyl carbodiimide as catalyst. The best condition ofexperiment obtained through single factor and orthogonal experiment is: the mole ratioof raw material and DCC is1:2.5(the mole ratio of DMAP·HCl,DMAP and DCC is 1:1.5:1); the ratio of raw material and THF is1g:560ml; the reaction temperature is80℃, the product yield was84%.In this route, raw materials are easier to get, most of the reagents are cheap acidand alkali, less waste,and most of the solvent can be recycled.What’s more, thepost-processing and reaction process are simple, easy to realize industrialization.