CN1015710B - 黄皮酰胺的制备方法 - Google Patents

黄皮酰胺的制备方法

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CN1015710B
CN1015710B CN86107090A CN86107090A CN1015710B CN 1015710 B CN1015710 B CN 1015710B CN 86107090 A CN86107090 A CN 86107090A CN 86107090 A CN86107090 A CN 86107090A CN 1015710 B CN1015710 B CN 1015710B
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methyl
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phenylpyrrolidine
ketone
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CN86107090A (zh
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沃尔夫冈·哈特维希
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Chinese Academy of Medical Sciences CAMS
Bayer AG
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    • C07D207/00Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom
    • C07D207/02Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom
    • C07D207/18Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having one double bond between ring members or between a ring member and a non-ring member
    • C07D207/22Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having one double bond between ring members or between a ring member and a non-ring member 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
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    • C07D207/02Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom
    • C07D207/18Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having one double bond between ring members or between a ring member and a non-ring member
    • C07D207/22Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having one double bond between ring members or between a ring member and a non-ring member 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
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    • C07D207/22Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having one double bond between ring members or between a ring member and a non-ring member 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
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Abstract

本文叙述了制备具有下式I结构的黄皮酰胺(clausenamide)的新的合成路线。已经发现,使下式II化合物氧化,可以得到立体化学上合适构型的产物-黄皮酰胺。本文还合成了用于黄皮酰胺全合成中的若干新化合物。这些化合物的通式是(A)式(A)中R是

Description

本发明是关于(±)3(S*),4(R*),5(R*), 7(S*)-3-羟基-5-α-羟苄基-1-甲基-4-苯基-吡咯烷-2-酮(黄皮酰胺(clausenamide))的制备方法。
已经知道,芸香料黄皮属植物anicata在非州一些地区作为民间药物使用〔J.Mester等,Planta    Medica    32,81(1977)〕。也已经知道,小叶黄皮的粗提取物对心血管有作用,并且用薄层层析从黄皮属pentaphalla(Ro×b)分离出的两种香豆素衍生物,clausmarin    A和B,具有解除痉挛的作用〔Dhan    Prakash等,J.Chem.Soc.Chem.Commun    1978,281〕。此外,在中国的中草药中,黄皮属叶子的水提取物被认为是有效的保肝药物,并用来治疗急性和慢性病毒性肝炎。已经能够从这种提取物中分离出作为主要组分之一的(±)3(S*),4(R*),5(R*),7(S*)-3-羟基-5-α-羟苄基-1-甲基-4-苯基-吡咯烷-2-酮(式Ⅰ,黄皮酰胺)。
Figure 86107090_IMG8
在动物试验中,黄皮酰胺显示抗遗忘作用和防止大脑缺氧的作用。因为进一步的药理学试验需要较大量的黄皮酰胺,同时,从植物中提取的方法又十分昂贵,从4公斤干燥的叶子中只能得到1.5克黄皮酰胺,所以提供化学合成黄皮酰胺的方法是必要的。
本发明是叙述制备(±)3(S*),4(R*),5(R*),7(S*)-3-羟基-5-α羟苄基-1-甲基-4-苯基-吡咯烷-2-酮(Ⅰ)的方法,该方法的特点是在碱存在时,在惰性有机溶剂中,如果合适,可用适当的辅助剂,使(±)4(R*),5(R*),7(S*)-5-α-羟苄基-1-甲基-4-苯基吡咯烷-2-酮(式Ⅱ)氧化。
Figure 86107090_IMG9
借助本发明的方法,可以只生成“正确的”C3-C4-反式构型羟基化产物(Ⅰ),并且产率很高,这一结果显然使人感到十分惊奇。产物和从植物提取物中得到的黄皮酰胺是相同的。和提取方法相比较,新方法在较短时间内可制得较大量产物,同时,成本低。除此之外,新方法还避免了具有其他活性的植物成份的混杂,而除去这些活性物质是很困难的。
用下面的反应式代表该反应过程:
能够使用的氧化剂是有机或无机过氧化物,例如过氧乙酸,氯代过苯甲酸或过氧化钼/吡啶络合物,此外还有氧,臭氧或氧转移剂,例如,2-磺酰基-氧氮丙啶(2-Sulphonyl    oxaziridine)。
可以应用的溶剂是在反应条件下不会变化的常用的惰性有机溶剂。优先选用的溶剂包括烃类(如苯、甲苯、二甲苯、己烷、环己烷或石油馏分),醚类(如***、四氢呋喃或二噁烷),醇类(如甲醇、乙醇或丙醇),卤代烃类(如二氯甲烷、氯仿、四氯化碳或1,2-二氯乙烷),冰醋酸,乙腈或六甲基磷酸三酰胺。也可以应用上述溶剂的混合物。
普通的碱类可以用作形成烯醇式盐所需要的碱。优先选用的碱包括碱金属醇化物,碱金属氨,碱金属氢化物或有机碱金属化合物,如甲醇钠或甲醇钾、乙醇钠或乙醇钾、叔-丁醇钾、氢化钠、氨基钠、二异丙基氨基锂、丁基锂或苯基锂;也可以应用叔胺,如1,5-二氮杂双环(4·3·0)壬-5-烯或1,8-二氮杂双环(5·4·0)十一-7-烯。碱最好是二异丙基氨基锂、六甲基哌啶锂和正、仲或叔丁基锂或苯基锂。
碱、溶剂的选择,以及需要时所需辅助试剂的选择,都取决于所选用的氧化方法。
如果需要应用辅助剂,尤其当过氧化钼/吡啶或氧用作氧化剂时,应用的辅助剂是能够还原在反应中形成氢过氧化物中间体阶段的物质。为此,最好应用亚磷酸酯,尤其是三烷基或三芳基亚磷酸酯,如亚磷酸三甲酯、亚磷酸三乙酯、亚磷酸三丙酯、亚磷酸三异丙酯、亚磷酸三丁酯或亚磷酸三苯酯。
在六甲基磷酸三酰胺中用过氧化钼/吡啶和氧进行氧化作用特别合适,在每种情况下都应用亚磷酸酯作为辅助剂。应用亚磷酸三乙酯作辅助剂,用氧在溶剂,如四氢呋喃或六甲磷酸三酰胺中,或在混合溶剂中进行氧化作用,可以得到很高的产率。已经证明,应用二异丙基氨基锂或丁基锂作为碱,是有利的。
反应温度可以在-100℃和+20℃之间变动,反应最好是在-78℃和0℃之间进行。
根据本发明的方法,羟基化反应能够在常压或 在加压或减压下进行,一般在常压下进行。
执行本发明的方法时,对于每摩尔原料化合物,可使用1到5摩尔,最好1到2.5摩尔的碱和0.5到5摩尔,最好为0.5到2摩尔的辅助剂。
化合物Ⅱ的烯醇式盐通常首先在最合适的溶剂中借助于碱来制得,同时将干燥的氧通入溶液,并加入亚磷酸酯,直到用薄层层析检查,观察不到进一步的变化为止。用专家所熟悉的一般方法处理反应混合物。
起始原料化合物(式Ⅱ)是新的。它能够用以下方法制备。在此方法中(±)4(R*),5(R*)-5-甲酰基-1-甲基-4-苯基-吡咯烷-2-酮(式Ⅲ)和金属有机化合物(如格氏试剂、有机钛或锂)反应,反应在适当的溶剂中进行,温度范围从-20℃到+50℃,最好在-10℃到+30℃之间,若是条件适宜,在碳原子7上发生异构化。
特别适合于该反应的金属有机化合物是苯基溴化镁、苯基氯化镁或苯基-三异丙氧基钛。
适合的有机溶剂是通常用于与格氏试剂或其他有机金属试剂反应的所有惰性有机溶剂,包括有醚类,例如可以优先选用***或四氢呋喃,如合适的话,它们可与己烷混合使用。
反应可按文献中类似的方法操作,例如可以参照以下文献的方法,D.Seebach,B.Weidmann和L.Widler:“Modern    Synthetic    Methods    1983”第217页及其后页(Verlag    Salle    und    Sauer    Lander)或在Houben-Weyl编的“Methoden    der    Organischen    Chemie”第ⅩⅢ/2a卷,第289页和第302页及其后页,或N.L.Drake和G.B.Coo-ke:Organic    Synthesis”第Ⅱ卷第406页及其后页(1963)。
根据使用的有机金属试剂的性质,能够首先形成在碳原子7上R*-构型的(±)4(R*),5(R*),7(R*)-5-α-羟苄基-1-甲基-4-苯基-吡咯烷-2-酮(式Ⅱa),
Figure 86107090_IMG12
然后通过氧化,异构化形成(±)4(R*),5(R*)-5-苯甲酰基-1-甲基-4-苯基吡咯烷-2-酮(Ⅳ)
Figure 86107090_IMG13
接着,还原Ⅳ,得到7-S*-构型产物(Ⅱ)
Ⅱa氧化到Ⅳ可用类似的已知方法进行,用二甲基亚砜作氧化剂,加入酸酐,尤为合适的是三氟乙酸酐,在适合的有机溶剂中反应,尤为合适的有机溶剂是卤代烃类,例如二氯甲烷或氯仿,或烃类,例如苯、甲苯、二甲苯或己烷,或者醚类,例如***、二氧六环或四氢呋喃,或上述溶剂的混合物,如S.L.Huang,K.Omura和D.Swern在“Synthesis”1980年,第297页所叙述的。
Ⅳ还原为Ⅱ能够使用通常惯用的还原剂。金属氢化物和复合金属氢化物尤为合适,例如四氢硼酸锂(Lithium    boranate),硼酸氢锂盐(Lithium    hydridoborates),硼烷酸氢钠盐,硼氢化合物,铝酸氢钠盐,铝酸氢锂盐或氢化锡尤其适合该反应。硼酸氢锂盐,例如三乙基硼酸氢锂或三(1-甲基丙基)硼酸氢锂或硼氢化钠更好。
合适的溶剂是用氢化物进行还原反应时常用的惰性有机溶剂。以醚类,例如***和四氢呋喃为最好。还原反应按类似的已知方法进行〔W.Friedrich    sen在Houben-Wey1编的“Methoden    der    Organi    Schen    Chemie”卷Ⅷ/1b,第145页及其后页;和H.C.Brown,S.Krishnamurthy:Chem.Co-mmun.1972年,第868页〕。
化合物(Ⅱa)也能够用类似已知的操作方法使异构化,例如按O.Mitsunobu在“Synthesis”1981,第1页上叙述的方法。
下列反应式能够图示化合物Ⅱ的制备过起:
假如使用苯基-溴化镁作金属有机试剂,几乎只生成“不正确的”构型Ⅱa,并可以上述方式异构化形成“正确的”构型Ⅱ。
本发明也记述了三个新化合物(式Ⅱa,Ⅳ和Ⅲ)的制备方法。式Ⅲ的醛能够按下列反应式制备:
Figure 86107090_IMG15
根据上述反应式,5,5-二乙酯基-4-苯基吡咯烷-2-酮(Ⅴ)用甲基化试剂,按反应步骤a进行甲基化。可用的甲基化试剂有溴甲烷,碘甲烷,对甲苯磺酸甲酯,重氮甲烷或硫酸二甲酯。如合适的话,反应可在碱(例如金属钠,氢化钠,氨基化钠,丁基锂或二异丙基氨基锂)存在下进行。反应可在合适的溶剂(如***,四氢呋喃,二甲基甲酰胺或六甲基磷酸三酰胺)中进行。温度可达-20℃到+80℃,最好为0℃到+40℃。在二甲基甲酰胺中用碘甲烷进行甲基化尤其适宜。已经证明,氢化钠作为碱用于此反应是有利的。可按专家所熟悉的普通方法来进行反应和处理产物。
在反应步骤b中,按P.Pachaly在Chem.Bdr.104(2),412-39(1971)中叙述的类似方法,使5,5-二乙酯基-1-甲基-4-苯基-吡咯烷-2-酮(Ⅵ)水解和脱羧,得到异构体Vlla和Vllb的混合物。通过重结晶或层析方法分离顺/反异构体Vall和b以后,Vlla被还原成(±)4(R*),5(R*)-5-羟甲基-1-甲基-4-苯基-吡咯烷-2-酮(Vlll)(反应步骤c)。
用与上述还原Ⅳ为Ⅱ相同的方法和条件,将Ⅶa还原为Ⅷ。
用与上述氧化Ⅱa到Ⅳ相同的方法和条件,将Ⅷ氧化为Ⅲ(反应步骤d)。
起始化合物Ⅴ是已知化合物〔G.H.Cocolas,W.H.Hartung,J.Am.Chem.Soc.79,5203(1957);和F.Zyma    lkowski,P.Pachaly,Chem.Ber.100,1137(1967)〕。
黄皮酰胺及其所有新的中间体的整个合成过程列于如下反应式:
Figure 86107090_IMG16
Figure 86107090_IMG17
制备例
实例1
(±)5,5-二乙酯基-4-苯基吡咯烷-2-酮
Figure 86107090_IMG18
在室温和氮气流下,将含有18克(0.8克原子)金属钠的400毫升无水乙醇溶液滴加到1.6升无水乙醇和432克(2摩尔)乙酰氨基丙二酸二乙酯组成的悬浮液中。缓:加入564克(3.2摩尔)肉桂酸乙酯,然后在沸点温度加热混合物24小时。
反应完成后,让混合物降至室温,加入2.5升氯仿,用乙酸中和混合物。用水彻底清洗(每次用500毫升,洗5次),然后经MgSO4干燥,用旋转蒸发器浓缩。用少量丙酮溶解油状残留物,加入己烷直到有结晶析出,继续加入己烷,到滴入处观察不到混浊现象为止。抽气过滤,得到标题化合物398克(54%),熔点为97-99℃。母液经层析(甲苯/乙酸乙酯),又得到标题化合物85克(14%),总共得到413克(68%)。
红外光谱(KBr):γ=1770(酯)1700(酰胺),1H-核磁共振谱(300MHz,CDCl3):δ=0.84和1.28(在每种情况下:t,J=7.5Hz;6H,CH2CH3);ABX***:δA=2.63,δB=2.96(JAB=17.3Hz,JAX=6Hz,JBX=9Hz;2H,C(3)-H);3.66和3.71(在各种情况下:m,2H,顺-CH2CH3);4.28(m,2H,反-CH2CH3);4.39(dd,JAX=6Hz,JBX=9Hz,1H,C(4)-H);6.95(br,1H,NH);和7.39(br,5H,C6H5)。
实例2
(±)5,5-二乙酯基-1-甲基-4-苯基-吡咯烷-2-酮
Figure 86107090_IMG19
在室温和N2气流下,将含有100克(0.33摩尔)(±)5,5-二乙酯基-4-苯基吡咯烷-2-酮的500毫升无水二甲基甲酰胺的溶液滴加到9.64克(0.36摩尔)氢化钠和200毫升二甲基甲酰胺组成的悬浮液中。在室温下搅拌,直至气体停止产生为止,然后加入含有93.7克(0.66摩尔)碘甲烷的50毫升无水二甲基甲酰胺溶液,室温下搅拌混合物,直到起始反应物已经全部反应完(大约1小时,用薄层层析检查)。将反应混合物倒入2升缓冲溶液(pH=7)中,然后用***萃取5次,每次用***600毫升。用MgSO4干燥有机萃取液,真空蒸发去除溶剂,得到105克(99.6%)标题化合物(根据1H-NMR核磁共振光谱,纯度95%),该纯度产物即可直接用于下一步的反应。为了分析,样品在球管中蒸馏,沸点0.5∶240℃,Rf=0.36(甲苯/乙酸乙酯:2/1)。
红外光谱(膜)γ=1735(酯),1700(酰胺),1H-核磁共振光谱(500MH2,CDCl3):δ=0.9和1.33(在各种情况下:t,J=7.5Hz;6H,CH2CH3);ABX***δA=2.66,δB=3.0(JAB=18Hz,JAX=6Hz,JBX=8.3Hz;2H,C(3)-H);3.06(S;3H,N-CH3);3.62和3.79(在各种情况下:m,2H,顺-CH2CH3);4.31(m,3H,反-CH2CH3)和C(4)-H)和7.26(M,5H,C6H5)。
实例3
(±)4(R*),5(R*)(I)和(±)(R*),5(S*)-5-乙酯基-1-甲基-4-苯基吡咯烷-2-酮(Ⅱ)
将49.5克(0.156摩尔)八水合氢氧化钡加到483毫升蒸馏水中,在70℃加热至几乎得到澄清的溶液。加入含有100克(0.313摩尔(±)5,5-二乙酯基-1-甲基-4-苯基-吡咯烷-2-酮的742毫升乙醇溶液,然后在700℃下搅拌混合物20分钟,直至起始原料已经全部反应(大约20分钟,用薄层层析检查)。冷却混合物,在冰冷却下酸化溶液到pH=1-2,在30℃-40℃浴温上减压除去乙醇。滤集得到固体,水相中加入氯化钠,用乙酸乙酯萃取3次,每次用200毫升。干燥有机萃取液,除去溶剂得到残留物和上述得到的固体合并,将其置于真空干燥中,在P4O10上高真空干燥24小时。固体物在充分搅拌下在油浴上加热到170℃,直到不再产生气体(5-10分钟)。冷却并进行快速层析分离(环己烷/乙酸乙酯=1/1,最后用乙酸乙酯)得到39.3克(50.7%)的(Ⅰ)(Rf=0.1)和19.6克(25.3%)的(Ⅱ)(Rf=0.20)(两种情况都是用环己烷/乙酸乙酯=1/1)。
红外光谱(KBr):δ=1736,1690Cm-1
1H-核磁共振谱(200MHz,CDCl3):Ⅰ:δ=0.83(t,J=7.5Hz;3H,CH2CH3)ABX***:δA=2.67,δB=2.95(JAB=17.5Hz,JAX=9Hz,JBX=10Hz;2H,(C(3)-H);2.87(S,3H,N-CH3),3.75(m,2H,CH2CH3),3.91(q,J=9-10Hz,1H,C(4)-H),4.36(d,J=9Hz,1H,C(5)-H),7.28(m,5H,C6H5)。Ⅱ:δ=1.30(t,J=7.5Hz,3H,CH2CH3);ABX***:δA=2.54,δB=2.82(JAB=18.5Hz,JAX=5Hz,JBX=9Hz,2H,C(3)-H),3.80(S,3H,N-CH3),3.53(ddd,J=9Hz,J=5Hz,J=4Hz,1H,C(4)-H),4.07(d,J=4Hz,1H,C(5)-H),4.27(m,2H,CH2-CH3)7.3(m,5H,C6H5)。
实例4
(±)4(R*),5(R*)-5-羟甲基-1-甲基-4-苯基吡咯烷-2-酮
Figure 86107090_IMG21
在-15到-20℃,在N2气流下,将0.317摩尔LiB(Et)3H(为316.9毫升在四氢呋喃中的1M溶液)滴加到含有39.2克(0.159摩尔)顺式-4(R*),5(R*)-5-乙酯基-1-甲基-4-苯基吡咯烷-2-酮的390毫升无水四氢呋喃溶液中。
接着将反应混合物在0℃搅拌1小时,倒入约200毫升用冰冷却了的2N盐酸中,用乙酸乙酯萃取2次,每次200毫升。水相用氯化钠饱和,并用乙酸乙酯萃取2次,每次200毫升。所收集的有机萃取液用少量水洗涤,经MgSO4干燥,在旋转蒸发器中浓缩,残留物用少量***使其结晶,然后用戊烷使其析出,直至在滴加处未见混浊现象为止。抽气过滤,干燥,得到标题化合物29.1克(89.2%),熔点为93-95℃。
红外光谱(KBr):γ=3324,1687cm-1
1H-核磁共振谱(300MHz,CDCl3):δ=ABM***的AB部分,δA=2.59,δB=2.97(各种情况下:dd,JAB= 15Hz,JAM=7.5Hz,JBM=9Hz,2H,C(3)-H);2.97(S,3H,N-CH3)ABM***的AB部分,δA=3.36,δB=3.62(各种情况下dd,JAB=11.2Hz,JAM=JBM=3Hz,2H,C(7)-H;3.72-3.85(m,2H,C(4)-H,C(5)-H);7.32(m,5H,C6H5)。
实例5
(±)4(R*),5(R*)-5-甲酰基-1-甲基-4-苯基吡咯烷-2-酮
Figure 86107090_IMG22
在温度为-60℃,在N2气流下,用10分钟时间,将含有29.7毫升三氟乙酸酐的56毫升无水二氯甲烷溶液滴加到含有19.9毫升(0.28摩尔)无水二甲基亚砜的140毫升无水二氯甲烷溶液中。在同样温度下搅拌15分钟,滴加含有28.8克(0.140摩尔)4(R*),5(R*)-5-羟甲基-1-甲基-4-苯基吡咯烷-2-酮的250毫升二氯甲烷溶液,温度不超过-60℃。接着在-60℃下搅拌90分钟,短时将其温热到-30℃(5-15分钟),然后再冷却到-60℃。在此温度下,缓:加入56毫升无水三乙胺,在-60℃搅拌混合物30分钟,然后温热到室温。加入600毫升水,使分成两相,水相用二氯甲烷萃取3次,每次250毫升。收集的有机萃取液用水洗涤2次,每次300毫升。经硫酸镁干燥并蒸馏。得到28.3克(100%)标题化合物,其Rf=0.25(乙酸乙酯),1H核磁共振谱测定纯度为91%。这样得到的粗产物,在干燥之后(高真空,24小时),即可直接用于下一步反应。
红外光谱(CHCl3):γ=1734,1689cm-1
1H-核磁共振谱(300MHz,CDCl3):δ2.79(dd,J=5.3Hz,J=9.7Hz,2H,C(3)-H);2.91(S,3H,N-CH3);4.02(q,J=9.7Hz,1H,C(4)-H);4.30(dd,J=1Hz,J=9.7Hz,1H,C(5)-H;7.3(m,5H,C6H5),9.17(d,J=1Hz,1H,CHO)。
实例6
(±)4(R*),5(R*),7(R*)-5-α-羟苄基-1-甲基-4-苯基吡咯烷-2-酮
在N2气流下,将含有24.8克(16.7毫升,0.156摩尔)溴苯的44毫升无水四氢呋喃溶液滴加到3.84克Mg屑上,使四氢呋喃缓:沸腾。然后加入100毫升无水四氢呋喃,加热回流,直至镁屑全部溶解(1-2小时)。
混合物被冷至0℃,在激烈搅拌下,滴加含有24.7克(0.12摩尔)4(R*),5(R*)-5-甲酰基-1-甲基-4-苯基吡咯烷-2-酮的250毫升无水四氢呋喃溶液,使温度不超过5℃。为了便于更充分地搅拌,必要时须加入无水四氢呋喃。然后将反应混合物在0℃到5℃搅拌1小时,倒入350毫升0.5NHC1-冰水中,用乙酸乙酯萃取4次,每次用300毫升,并用二氯甲烷萃取2次,每次用300毫升。收集的乙酸乙酯和二氯甲烷萃取液(要分开!)分别用水洗涤2次,每次用水200毫升合并的萃取液经硫酸镁干燥。真空除去溶剂后剩下的残留物,加入100毫升***研磨至出现结晶,然后慢慢加入500毫升戊烷混合物置于冰箱中过夜。抽气过滤,得到25克(74.3%)标题化合物,熔点为210-212℃。
为了分析,将产物在丙酮中再结晶,熔点为214-5℃。
红外光谱(KBr)γ=3362(br),1654cm-1
1H-核磁共振光谱(300MHz,d6-DMSO):δ=2.21,(S,3H,NCH3);2.24(dd,ABM***A部分,JAB=15.7Hz,JAM=9.4Hz,1H,顺式-C(3)-H);3.05(dd,ABM***B部分,JBM=12.7Hz,1H,反式-C(3)-H),3.80(dt,ABM***M部分,JAM=8.5Hz,JAB=12.7Hz,J4.5=8.5Hz,1H,C(4)-H);4.15(dd,J=8.5Hz,J=1Hz,1H,C(5)-H);4.26(dd,J=6Hz,J=1Hz,1H,C(7)-H);5.35(d,J=6Hz,1H,OH);7.15-7.5(m,10H,C6H5)。
实例7
(±)4(R*),5(R*)-5-苯甲酰基-1-甲基-4-苯基吡咯烷-2-酮
Figure 86107090_IMG24
于-60℃,在N2气流下,用10分钟时间,将含有18毫升三氟乙酸酐的34毫升无水二氯甲烷溶液滴加到12.24毫升(0.171摩尔)无水二甲基亚砜在87毫升无水二氯甲烷的溶液中。接着在相同的温度下将混合物搅拌15分钟,并滴加含有24克(0.085摩尔)4(R*),5(R*),(7R*)-5-α-羟苄基-1-甲基-4-苯基吡咯烷-2-酮的大约700毫升无水二氯甲烷溶液,使温度不要超过-60℃。将混合物在-60℃搅拌90分钟。短时温热到-30℃(9-10分钟),然后再冷到-60℃。在此温度下,缓:加入34.2毫升三 乙胺,混合物在-60℃搅拌20分钟,然后升温到室温。加入370毫升水,使分成两相,水相用二氯甲烷萃取3次,每次用230毫升。合并有机萃取液,用水洗涤2次,每次用水300毫升,经硫酸镁干燥,用旋转蒸发器浓缩。残留物加***在旋转蒸发器中蒸发2次,每次加200毫升***。得到标题化合物23.5g(100%),熔点为115-115℃。1H-核磁共振光谱分析,粗产品是纯的,即可直接用于下一步反应。
为了分析,在硅胶上进行层析分离制备样品,Rf=0.25(乙酸乙酯)熔点为121-2℃。
红外光谱(KBr):ν=1695,1682cm-1
1H-核磁共振光谱(300MHz,CDCl3):δ=2.78和2.91,(ABM***的AB部分,JAB=16.5Hz,JAM=JBM=8.3Hz,2H,C(3)-H);2.88(S,3H,N-CH3);4.02(q,J=8.3Hz,1H,C(4)-H);5.42(d,J=8.3Hz,1H,C(5)-H);7.0,7.21,7.59和7.50(各种情况下:m,10H,C6H5)。
实例8
(±)4(R*),5(R*),7(S*)-5-羟甲基苯基-1-甲基-4-苯基吡咯烷-2-酮
Figure 86107090_IMG25
于-15℃到-20℃,在N2气流下,滴加83毫摩尔LiB(Et)3H(83毫升的1M四氢呋喃溶液)到含有23克(82.3毫摩尔)4(R*),5(R*)-5-苯甲酰基-1-甲基-4-苯基吡咯烷-2-酮的200-270毫升无水四氢呋喃溶液中。然后反应混合物在0℃搅拌1小时,倒入100毫升用冰冷却的1NHCl中,加乙酸乙酯萃取2次,每次用200毫升。水相用氯化钠饱和,并用乙酸乙酯萃取2次,每次用200毫升。合并有机萃取液,经MgSO4干燥,在旋转蒸发器中浓缩。残留物溶解在二氯甲烷中,用水洗涤2次,每次100毫升。有机相用MgSO4干燥,在旋转蒸发器中浓缩,加100毫升***使残留物结晶,搅拌下缓:加入戊烷,直到在滴入处不出现混浊为止。抽滤沉淀物,干燥后,得到16.6克(72%)标题化合物,其熔点为189-195℃。
根据1H-NMR测定,产物纯度为95%,即可直接用于下一步反应。
为了分析的目的,产物在丙酮中再结晶(熔点为197-8℃)。
红外光谱(KBr):γ=3251,1692cm-1
1H-核磁共振光谱(300MHz,DMSO):δ=1.97和2.05(ABM***,JAB=13.5Hz,JAM=8.2Hz,JBM=13Hz,2HC(3)-H);2.91(S3H,N-CH3);3.82(dt,JAM=J4.5=8.2Hz,JBM=13Hz,1H,C(4)-H);4.27(dd,J=8.2Hz,J=1.5Hz,1H,C(5)-H);4.65(dd,J=1.5Hz,J=3.5Hz,1H,C(7)-H);5.34(d,J=3.5Hz,1H,OH);6.70,7.11和7.25各种情况下:m,10H,C6H5)。
实例9
(±)3(S*),4(R*),5(R*),7(S*)-3-羟基-5-α-羟苄基-1-甲基-4-苯基吡咯烷-2-酮(黄皮酰胺)
Figure 86107090_IMG26
将含有17.7克(62.8毫摩尔)4(R*),5(R*),7(S*)-5-α-羟苄基-1-甲基-4-苯基吡咯烷-2-酮的490毫升无水四氢呋喃和130毫升无水六甲基磷酸三酰胺的溶液置于烧瓶中,这个烧瓶已经在抽真空时充分加热,并用纯氮冲洗过的。冷却该溶液到-70℃,在此温度下,滴加含有0.152摩尔二异丙基氨基锂(Lithium diisopro pylamide)的180毫升无水四氢呋喃/己烷溶液(此溶液制备方法:于-20℃到0℃,在含有22.1毫升二异丙胺的80毫升四氢呋喃溶液中,加入103毫升1.5N正丁基锂己烷溶液)。接着,在-70℃到-60℃搅拌混合物1小时,加入5.3毫升新蒸馏的亚磷酸三甲酯(溶解于少量无水四氢呋喃中),通入干燥的氧(用浓H2SO4与P4O10干燥)(50-100毫升/分钟)。根据薄层层析检查(SiO2;展开剂为乙酸乙酯/甲醇=2/1;产物Rf=0.3,起始化合物Rf=0.37,用磷钼酸喷雾剂显色),一旦发现产物/起始化合物比值不再改变时(2-3小时)用冰冷却下将混合物倒入600毫升0.5NHCl中,必要时将其酸化到pH3-4。
溶液分成两相,水相用乙酸乙酯萃取4次,每次300毫升。合并有机萃取液,用水洗3次,每次用水300毫升,经MgSO4干燥,用旋转蒸发器浓缩。浓缩残留物溶于50-100毫升***中,搅拌混合物直至开始出现结晶,在搅拌下加入戊烷,直到在滴加处不再观察到混浊为止。混合物在冰箱中放置过夜,然后抽气过滤。得到17克粗的固体产物,除了标题化合物外,还含有35-40%的起始原料。为了纯化,粗产物在甲醇中重结晶2次,得到纯度约95%的标题化合物。在氧化铝(中性上进行层析分离,不损失产物还能回收纯的 起始原料。为此目的,粗产物吸附在硅胶上(加热使粗产物溶解于甲醇中,加入5份重量的硅胶;在旋转蒸发器中浓缩,加入乙酸乙酯到旋转蒸发器中,几次蒸发,直到成为不含甲醇的粉状为止)。将吸附物干粉装入有Al2O3(中性,50份重)的柱中,首先用乙酸乙酯洗,脱起始原料(快速层析分离,薄层层析)检查,高压液相色谱分析)。然后用乙酸乙酯/甲醇混合液(40/1,20/1然后用10/1)洗脱标题化合物。得到8.6克(46.1%)产物,其熔点为236-7.5℃(实际黄皮酰胺的熔点为236-7℃),纯度约98%(根据1H-NMR,产物含有约2%的起始原料)。能够回收5克纯的起始原料。
红外光谱(KBr):γ=3402,3321,1689cm-1
1H-核磁共振光谱(300MHz,DMSO):δ=3.01(S,3H,N-CH3);3.50(dd,J=8Hz,J=10.5Hz,1H,C(4)-H);3.82(dd,J=10Hz,J=7Hz,1H,C(3)-H);4.30(dd,J=8Hz,J=2Hz,1H,C(5)-H);4.65(dd,J=2Hz,J=3Hz,1H,C(7)-H),5.39(d,J=7Hz,1H,C(3)-OH);5.45(d,J=3Hz,1H,C(7)-OH);6.61-6.64(m,2H,芳基H)和7.03-7.28(m,8H,芳基H)。

Claims (7)

1、制备按式(Ⅰ)的(±)3(S*),4(R*),5(R*),7(S*)-3-羟基-5-α-羟苄基-1-甲基-4-苯基吡咯烷-2-酮的方法,其特征在于在惰性有机溶剂中,于一种碱即二异丙基氨基锂存在下,并任选在亚磷酸酯类辅助剂存在下,用氧作为氧化剂,于-100℃至+20℃之间,对按式(Ⅱ)的(±)4(R*),5(R*),7(S*)-5-α羟苄基-1-甲基-4-苯基吡咯烷-2-酮进行氧化
Figure 86107090_IMG2
2、按照权利要求1所述的方法,其特征在于所述氧化是于-78℃至0℃进行的。
3、按照权利要求1所述的方法,其特征在于,所述氧化反应是在亚磷酸三甲酯存在下,在四氢呋喃或六甲基磷酸三酰胺或这些溶剂的混合物中进行的。
4、按权利要求1的方法,其中按式(Ⅱ)的原料化合物(±)4(R*),5(R*),7(S*)-5-α-羟苄基-1-甲基-4-苯基吡咯烷-2-酮是通过在惰性溶剂中用金属氢化物和复合金属氢化物还原按式(Ⅳ)的(±)4(R*),5(R*)-5-苯甲酰基-1-甲基-4-苯基吡咯烷-2-酮而制备的
Figure 86107090_IMG3
5、按权利要求4的方法,其中按式(Ⅳ)的(±)4(R*),5(R*)-5-苯甲酰基-1-甲基-4-苯基吡咯烷-2-酮是按下述方法制备的:
将按(式Ⅲ)的(±)4(R*),5(R*)-5-甲酰基-1-甲基-4-苯基吡咯烷-2-酮
Figure 86107090_IMG4
于-20至+50℃,在惰性有机溶剂中与金属有机化合物反应生成按式(Ⅱa)的(±)4(R*),5(R*),7(R*)-5-α-羟苄基-1-甲基-4-苯基吡咯烷-2-酮
Figure 86107090_IMG5
然后在有机溶剂中,在酸酐存在下,用二甲基亚砜作氧化剂,将式(Ⅱa)化合物氧化为式(Ⅳ)化合物。
6、按权利要求5的方法,其中按式(Ⅲ)的(±)4(R*),5(R*)-5-甲酰基-1-甲基-4-苯基吡咯烷-2-酮是通过在有机溶剂中,在酸酐存在下,用二甲基亚砜氧化按式(Ⅷ)的(±)4(R*),5(R*)-5-羟甲基-1-甲基-4-苯基吡咯烷-2-酮而制备的
Figure 86107090_IMG6
7、按权利要求6的方法,其中按式(Ⅷ)的(±)4(R*),5(R*)-5-羟甲基-1-甲基-4-苯基吡咯烷-2-酮是按下述方法制备的:
Figure 86107090_IMG7
步骤a)中按式(Ⅴ)的5,5-二乙酯基-4-苯基吡咯烷-2-酮的甲基化反应是在***、四氢呋喃、二甲基甲酰胺或六甲基磷酸三酰胺等溶剂中,在金属钠、氢化钠、氨基化钠、丁基锂或二异丙基氨基锂之类的碱存在下,于-20至+80℃进行,可用的甲基化试剂包括溴甲烷、碘甲烷、对甲苯磺酸甲酯、重氮甲烷或硫酸二甲酯等;
步骤b)中按式(Ⅵ)的5,5-二乙酯基-1-甲基-4-苯基吡咯烷-2-酮通过水解和脱羧反应,得到按式(Ⅶa)和(Ⅶb)的异构体混合物,
经异构体分离,通过在惰性溶剂中、用金属氢化物和复合金属氢化物还原式(Ⅶa)的(±)4(R*),5(R*)-5-乙酯基-1-甲基-4-苯基-吡咯烷-2-酮,得到式(Ⅷ)的(±)4(R*),5(R*)-5-羟甲基-1-甲基-4-苯基吡咯烷-2-酮。
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