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1、越般彭⑧天洋大謦中國(guó)近代第所大學(xué)碩士學(xué)位論文L'J-爿■●■■0●爿,}■■疆■■¨a____學(xué)科專(zhuān)業(yè):亙刖t學(xué)作者姓名:盂祥啟指導(dǎo)教師:張里塹豇教授壬津士堂研窯畢陴2006年1月摘要本論文是關(guān)于菊酯類(lèi)農(nóng)藥七氟菊酯的合成和工藝優(yōu)化的研究,重點(diǎn)優(yōu)化了重要中間體四氟對(duì)甲基芐醇的合成工藝,并對(duì)目標(biāo)產(chǎn)物七氟菊酯的合成路線進(jìn)行了改進(jìn)。以四氯對(duì)苯二甲酸為原料,經(jīng)酰氯化、氟化、酯化、還原、溴化、還原六步反應(yīng)合成了四氟對(duì)甲基芐醇。四氟對(duì)甲基芐醇再經(jīng)氯化、與(z).ORS,3RS).3.(2-氯·3,3,3-三氟丙-l一丙烯基)一2,2.二甲基
2、環(huán)丙甲酸(功夫酸)酯化合成了七氟菊酯。重點(diǎn)對(duì)工藝路線中溴化、還原反應(yīng)進(jìn)行了優(yōu)化。以甲苯為溶劑,四氟對(duì)苯二芐醇與氫溴酸反應(yīng)制得四氟對(duì)溴甲基芐醇,將氫溴酸的用量從四氟對(duì)苯二芐醇的摩爾量10倍降低至5倍,并且使產(chǎn)品收率從88.13%提高到90.07%。四氟對(duì)溴甲基芐醇被鎂粉和甲醇還原生成四氟對(duì)甲基芐醇,通過(guò)采用替代溶劑,將鎂粉的用量減少到原工藝的四分之一,收率由78%提高到96%。設(shè)計(jì)并采用四氟對(duì)甲基芐醇先氯化得到四氟對(duì)甲基芐基氯,收率為95.28%,再與功夫酸反應(yīng)制備七氟菊酯的新路線,收率為91.86%,避免了原工藝中價(jià)格昂貴的D
3、CC,產(chǎn)品純度大于96%。優(yōu)化后總收率從52.94%提高到60.10%,獲得了一條適合工業(yè)化合成七氟菊酯的工藝路線。關(guān)鍵詞:四氯對(duì)苯二甲酸四氟對(duì)苯二甲酸二甲酯四氟對(duì)甲基芐醇,四氟對(duì)甲基芐基氯,功夫酸,七氟菊酯ABSTRACT11碡synthesisoftefluthrin.whichisakindofpyrethroidpesticide,wasstudiedinthispaper.Thesyntheticprocess&thelefluthrinandthe4-methyl-2,3,5,6-tetrafluoro-tmnzy
4、lalcohol,a/iimportantintermediatefortefluthrin,wercimproved.4-Methyl·2,3,5,6.tetrafluoro·benzylalcoholwassynthesizedbyacylation,fluorination,esterifleation,reduction,bromizationandreductionfromtetracloro-tercphthalieacid.Tefluthrinwasobtainedfrom(Z)-(IRS,3RS卜3·(2-ch
5、loro一3,3,3一trifluom—l·pmpenyl)·22一dimethylcycolpropaneearboxylateacidbyreactingwith4-chlormethyi-2?356-tetrafluorotoluolwhichwaspreparedfrom4-methyl-2,3,5,6-tctrafluom·benzylalcoh01.ThereactionsofbromizationandreductioninthesyntheticprocessweTestudied.Tetrafluoroter
6、ephthalylalcoholwasbromatcdinthehydro·bromicacidtoobtain(4-(bromomethyl)-2。356-tetrafluorophenyl)methan01.Withtoluene鼢solvent,theamountofhydrobromicaciddecreasedfromtentimesofthetooloftetrafluomterephthalylalcoholtofivetimesandtheyieldincreasedfrom88.13%to90.07%.4-M
7、ethyl-2,3,5,6-tetrafluoro-benzylalcoholwasobtainedbyreducingthebromidewithmagnesiumandmethan01.Byreplacingmathanolwithdichlommethaneassolvent,theamountofmagnesiumdecreasedtoonefourthofthatinformermethodandtheyieldincreasedfrom78%to96%.Anewrouteoftefluthrinwasdesigne
8、d.4-Methyl-2?356一Tetrafluombenzylchloridewaspreparedfrom4-methyl-2,3,5,6-tetrafluoro-benzylalcoholandtheyieldwas91.86%.Thentefluthrinwasac