CN1015986B - 制备高纯乙交酯的方法 - Google Patents
制备高纯乙交酯的方法Info
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- CN1015986B CN1015986B CN87107549A CN87107549A CN1015986B CN 1015986 B CN1015986 B CN 1015986B CN 87107549 A CN87107549 A CN 87107549A CN 87107549 A CN87107549 A CN 87107549A CN 1015986 B CN1015986 B CN 1015986B
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D309/00—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings
- C07D309/02—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings having no double bonds between ring members or between ring members and non-ring members
- C07D309/08—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings having no double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D309/10—Oxygen atoms
- C07D309/12—Oxygen atoms only hydrogen atoms and one oxygen atom directly attached to ring carbon atoms, e.g. tetrahydropyranyl ethers
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D319/00—Heterocyclic compounds containing six-membered rings having two oxygen atoms as the only ring hetero atoms
- C07D319/10—1,4-Dioxanes; Hydrogenated 1,4-dioxanes
- C07D319/12—1,4-Dioxanes; Hydrogenated 1,4-dioxanes not condensed with other rings
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Polyesters Or Polycarbonates (AREA)
- Heterocyclic Compounds That Contain Two Or More Ring Oxygen Atoms (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Polyethers (AREA)
- Medicinal Preparation (AREA)
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Abstract
一种通过加热α-羟基酸或其酯在热稳定聚醚芯上形成的共聚物,制备高纯乙交酯的方法。
Description
本发明涉及高纯乙交酯以及通过加热α-羟基酸或其酯和热稳定聚醚的共聚物,制备高纯乙交酯的改进方法。采用真空蒸馏、溶剂萃取和重结晶纯化,可从反应混合物中分离出乙交酯。热稳定聚醚残余物可与新鲜α-羟基酸或其酯再循环,制取附加共聚物。
具有下述通式的环酯类是一种可聚合成高分子量聚合塑料的有效化合物,特别有用于医药用途,例如创伤闭合装置、矫形外科植入物和控制释放药物载体。所述环酯的通式为:
式中R1和R2可各自为氢或具有1至约6个碳原子的脂族烃基团。
以往,这些环酯的制备首先通过制取相应于环酯的α羟基酸的脆性聚合形式,例如,若所需产品是乙交酯,则将乙醇酸转化为聚乙醇酸的脆性聚合形式。然后,将聚合材料研磨至细粉,缓慢地加至热的抽空容器中,使之彻底解聚为必须经受充分和昂贵的纯化操作才能使用的原材料。这个过程的缺点是有过量焦油的形成、低产量和低的生产率。在授予Donald L.Ross的美国专利3,763,190号中介绍了一种试图改进热裂
化过程和制备较纯的乙交酯的方法。那个方法需要先制备0-卤乙酰乙醇酸的盐,然后把该盐加热至足够温度,以完成闭环。必须除去无机盐,并且分离生成的乙交酯,用升华进行纯化。
本发明方法是热裂化过程,不涉及卤代α-羟基酸的盐的形成。本发明不同于上述的以往那种热裂化过程,因为避免了过量焦油的形成,因此产量基本上较高,反应速率快得多,并且由于低的焦油形成,使本方法不但可间歇操作,而且还可连续操作。
本发明方法涉及首先制取包括热稳定聚醚芯与在其芯端上聚合的α-羟基酸或其酯的嵌段共聚物。在真空加热时,链端被热降解形成可真空缩合而剩下水或醇的环酯,和在残余热稳定聚醚中形成的焦油,该残余热稳定聚醚可与新鲜α-羟基酸或其酯再循环,制取附加共聚物。其次可热分解该共聚物,离析出附加环酯,然后用溶剂萃取和重结晶粗环酯,产生高纯产品。
本发明产品纯度高于其它迄今已知方法的产品。
本发明方法最初需要形成热稳定聚醚芯与在芯的每端聚合的α-羟基酸或其酯形成的嵌段共聚物,该热稳定聚醚可以是脂族的或芳族的聚醚。优选的脂族聚醚是像聚氧化亚甲(Teracol
)那种聚醚二醇,由E.I.du pont de Nemours and Company制造。这种聚醚二醇的分子量范围很宽,如市售的聚氧化亚甲分子量范围为650至2900。可以制得较高的分子量。分子量低于聚氧化亚甲的聚醚二醇也可使用。优选的分子量范围约为900至3000,最佳范围约为1800至2200。优选的芳族聚醚是亚苯基氧化物。α-羟基酸是式R1R2C(OH)COOH,式中R1和R2可各自为氢或带有1至6个碳原子的脂族烃基团。优选的α-羟基酸是乙醇酸和乳酸。α-羟基酸的酯是式R1R2C(OH)COOR3,式中R1和R2如α-羟基酸所定义,R3是带有1至6个碳原子的脂族烃基。优选的酯类是乙醇酸甲酯和乙醇酸乙酯,以及乳酸甲酯和乳酸乙酯。
在下文称为预聚物的热稳定聚醚和α-羟基酸的嵌段共聚物,可在最好是中性或碱性的聚合催化剂参加下,通过加热α-羟基酸或其酯和热稳定聚醚芯生成。此外,也可添加如碱土金属氧化物那样的不挥发碱,但不局限于此。例如,为制取预聚物,可在三氧化锑参加下,在175至225℃温度和25至250毫米汞柱压力下,加热聚氧化亚甲乙醇酸、乙醇酸和聚氧化亚甲。预聚物在这些条件下形成,离析出水和一些四氢呋喃(THF)。
预聚物温度升至足够高的温度,使α-羟基酸或其酯端热降解,这种解聚在真空中进行,并冷凝和收集离析出的粗环酯。这种解聚的适宜温度范围约为225至285℃,优选温度范围约235至265℃,进行这一操作步骤的真空范围约为1至25毫米汞柱,最好约为2至10毫米汞柱。该步骤还可在不挥发碱参加下操作。
离析的粗环酯可被溶剂萃取和重结晶,以达到高纯度。残余聚醚可以再使用,制取其他预聚物。
由于本发明方法使焦油的形成减至最少,以及可再循环残余聚醚,故本发明方法除间隙操作外,还可连续操作。在连续操作过程中,残余聚醚被再循环制取附加预聚物,在解聚中形成的微量焦油可溶于制备预聚物期间离析的溶剂中,这样可控制焦油含量,以避免在系统中积累。
由于焦油的形成减至最少,本发明方法有可能生产下式的环脂,比迄今生产的更纯。所述环脂的通式为:
式中R1和R2可各自为氢或带有1至6个碳原子的脂族烃基。
为了更充分理解本发明的构思,列举下述实施例,用以说明而不局限本发明。
实施例1
通过热分解聚氧化亚甲-羟基乙酸嵌段共聚物制备乙交酯
将200克再结晶羟基乙酸(HAA)加到400克聚氧化亚甲-1000(分子量-1000)和0.05克三氧化锑中。这个混合物在200℃和223毫米汞柱压力下,经共聚,得到预聚物并产生32克液体(约20%THF和80%水被离析)然后将生成的417.2克预聚物升温至280℃,真空提高至7毫米汞柱,在此后一个小时内收集102,9克粗乙交酯。该反应器再操作两小时,收集额外的25.5克粗乙交酯。额外的11.8克粗乙交酯被收集在阱里。一部分粗乙交酯(10.2克)用乙酸乙酯再结晶两次,得到含8.55克精制乙交酯产品,熔点测定表明其纯度为>99%。
实施例2
聚氧化亚甲制备乙交酯后的再利用
取254克实施例1的剩余物,与150克新鲜的重结晶HAA掺合。共聚步骤在165℃和140毫米Hg柱下重复,得到附加的预聚物,并产生21克液体(8%THF,91%水)。该预聚物再在250℃和4毫米汞柱下加热,回收得96克粗乙交酯。然后把这种产品的一部分(10.2克)用乙酸乙酯重结晶两次,得到8.52克精制乙交酯,熔点测定表明其纯度为>99%。
用已知化学方法制备乙交酯
在192℃和12毫米汞柱真空及有1克三氧化锑参加下,聚合100克无水HAA。把该产品研磨成细粉,缓慢地(2小时)加到220℃和8毫米汞柱真空的热容器中。从约34.3克细粉进料得到总计6.9克粗乙交酯。该粗产品用乙酸乙酯重结晶两次,得到4.1克精制乙交酯。反应器壁被未转化的HAA进料严重烧黑。熔点测定表明其纯度大约90%。
实施例4
由其它聚氧化亚甲制备乙交酯
200克无水HAA和400克聚氧化亚甲-1800(分子量=1800)与0.05克三氧化锑在215℃和4毫米汞柱下加热3小时,直至液体停止放出。除去产生总量为333毫升(75%THF,25%水)的液体。然后在10毫米汞柱下把预聚物加热至270℃,产生88克粗乙交酯。聚氧化亚甲的剩余物计165克。该粗产品用乙酸乙酯重结晶两次,得到75克精制乙交酯。其红外光谱与公布的文献一致,用热重分析(TGA)表明其纯度为>99%。C、H分析为C 41.6%和H 3.6%(理论值为41.4%和3.4%)。
Claims (7)
2、根据权利要求1的方法,其中热稳定聚醚芯是脂族聚醚。
3、根据权利要求2的方法,其中脂族聚醚是聚醚二醇。
4、根据权利要求3的方法,其中聚醚二醇的分子量为900至3000。
5、根据权利要求4的方法,其中聚醚二醇的分子量为1800至2200。
6、根据权利要求1的方法,其中溶剂是乙酸乙酯。
7、根据权利要求1的方法,进一步包括将权利要求1步骤b的热稳定聚醚残余物向步骤a再循环的附加步骤。
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
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US75390785A | 1985-07-11 | 1985-07-11 | |
US925,484 | 1986-10-29 | ||
US06/925,484 US4727163A (en) | 1985-07-11 | 1986-10-29 | Process for preparing highly pure cyclic esters |
Publications (2)
Publication Number | Publication Date |
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CN87107549A CN87107549A (zh) | 1988-05-11 |
CN1015986B true CN1015986B (zh) | 1992-03-25 |
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Application Number | Title | Priority Date | Filing Date |
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CN87107549A Expired CN1015986B (zh) | 1985-07-11 | 1987-10-28 | 制备高纯乙交酯的方法 |
Country Status (17)
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US (1) | US4727163A (zh) |
EP (1) | EP0266143B1 (zh) |
JP (1) | JPS63152375A (zh) |
KR (1) | KR880005116A (zh) |
CN (1) | CN1015986B (zh) |
AR (1) | AR243879A1 (zh) |
AT (1) | ATE102617T1 (zh) |
AU (1) | AU591432B2 (zh) |
BR (1) | BR8705758A (zh) |
CA (1) | CA1277672C (zh) |
DD (1) | DD264695A1 (zh) |
DE (1) | DE3789274D1 (zh) |
IE (1) | IE872885L (zh) |
IL (1) | IL84303A (zh) |
MX (1) | MX165197B (zh) |
PT (1) | PT86017B (zh) |
ZA (1) | ZA878121B (zh) |
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US2163268A (en) * | 1933-12-12 | 1939-06-20 | Du Pont | Method for making cyclic esters |
US2163109A (en) * | 1936-04-03 | 1939-06-20 | Du Pont | Chemical process and products therefrom |
US2668162A (en) * | 1952-03-20 | 1954-02-02 | Du Pont | Preparation of high molecular weight polyhydroxyacetic ester |
FR1485302A (fr) * | 1966-07-01 | 1967-06-16 | Wolfen Filmfab Veb | Procédé pour l'obtention d'esters-anhydrides cycliques d'acides alpha-hydroxy-carboxyliques |
US3442871A (en) * | 1966-05-04 | 1969-05-06 | American Cyanamid Co | Process for polymerizing a glycolide |
GB1108720A (en) * | 1966-10-10 | 1968-04-03 | Wolfen Filmfab Veb | Process for the manufacture of cyclic ester anhydrides of ª-hydroxy-carboxylic acids |
US3457280A (en) * | 1967-06-12 | 1969-07-22 | American Cyanamid Co | Alpha-glycolide and methods for the isolation thereof |
US3435008A (en) * | 1967-08-22 | 1969-03-25 | American Cyanamid Co | Method for preparation of isomerically pure beta-glycolide and polymerization method for glycolide compositions employing partial hydrolyzate of said beta-glycolide |
US3597350A (en) * | 1968-11-12 | 1971-08-03 | Pharmacia Fine Chemicals Ab | Gel filtration process |
US3763190A (en) * | 1972-04-19 | 1973-10-02 | Stanford Research Inst | Preparation of pure glycolide |
-
1986
- 1986-10-29 US US06/925,484 patent/US4727163A/en not_active Expired - Fee Related
-
1987
- 1987-10-22 CA CA000549976A patent/CA1277672C/en not_active Expired - Lifetime
- 1987-10-26 DE DE87309416T patent/DE3789274D1/de not_active Expired - Lifetime
- 1987-10-26 EP EP87309416A patent/EP0266143B1/en not_active Expired - Lifetime
- 1987-10-26 AT AT87309416T patent/ATE102617T1/de not_active IP Right Cessation
- 1987-10-28 JP JP62272900A patent/JPS63152375A/ja active Pending
- 1987-10-28 AR AR87309150A patent/AR243879A1/es active
- 1987-10-28 BR BR8705758A patent/BR8705758A/pt unknown
- 1987-10-28 IE IE872885A patent/IE872885L/xx unknown
- 1987-10-28 MX MX9002A patent/MX165197B/es unknown
- 1987-10-28 AU AU80417/87A patent/AU591432B2/en not_active Ceased
- 1987-10-28 DD DD87308357A patent/DD264695A1/de not_active IP Right Cessation
- 1987-10-28 IL IL84303A patent/IL84303A/xx not_active IP Right Cessation
- 1987-10-28 CN CN87107549A patent/CN1015986B/zh not_active Expired
- 1987-10-28 PT PT86017A patent/PT86017B/pt not_active IP Right Cessation
- 1987-10-28 KR KR870011957A patent/KR880005116A/ko not_active Application Discontinuation
- 1987-10-29 ZA ZA878121A patent/ZA878121B/xx unknown
Also Published As
Publication number | Publication date |
---|---|
PT86017A (en) | 1987-11-01 |
US4727163A (en) | 1988-02-23 |
IL84303A0 (en) | 1988-03-31 |
JPS63152375A (ja) | 1988-06-24 |
IL84303A (en) | 1993-01-14 |
KR880005116A (ko) | 1988-06-28 |
ZA878121B (en) | 1989-07-26 |
DE3789274D1 (de) | 1994-04-14 |
MX165197B (es) | 1992-10-30 |
IE872885L (en) | 1988-04-29 |
AR243879A1 (es) | 1993-09-30 |
BR8705758A (pt) | 1988-05-31 |
ATE102617T1 (de) | 1994-03-15 |
CA1277672C (en) | 1990-12-11 |
AU8041787A (en) | 1988-05-05 |
EP0266143A3 (en) | 1990-03-07 |
CN87107549A (zh) | 1988-05-11 |
PT86017B (pt) | 1990-07-31 |
AU591432B2 (en) | 1989-11-30 |
DD264695A1 (de) | 1989-02-08 |
EP0266143A2 (en) | 1988-05-04 |
EP0266143B1 (en) | 1994-03-09 |
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