2-(2′-乙酰氧基-5′-溴甲基苯基)-2H-苯并三唑的合成

2-(2′-羟基-5′-甲基苯基)-2H-苯并三唑(UV-P)经过羟基乙酰化、N-溴代丁二酰亚胺(NBS)溴代,合成了具有高反应活性的2-(2′-乙酰氧基-5′-溴甲基苯基)-2H-苯并三唑。为提高目标产物产率和反应效率,分别对溶剂、引发剂、反应温度、反应时间、反应物投料比和反应底物浓度进行了研究。得出较优合成条件为:氮气保护下,四氯化碳为溶剂,偶氮二异丁腈(AIBN)引发,NBS与2-(2′-乙酰氧基-5′-甲基苯基)-2H-苯并三唑摩尔比1∶1,回流反应1h。在上述条件下,2-(2′-乙酰氧基-5′-溴甲基苯基)-2H-苯并三唑产率为60%。产物经过IR、1HNMR、MS分析证明结构正确。     

2-溴-1-(3,4,5,-三甲氧基苯基)-乙酮的合成

以3,4,5-三甲氧基苯乙酮为原料,用N-溴代丁二酰亚胺(NBS)为溴化物合成2-溴-1-(3,4,5,-三甲氧基苯基)-乙酮。考察不同反应溶剂、不同反应温度和不同NBS用量以及是否添加催化剂等不同反应条件对产率的影响。溶剂为乙醇时,反应温度为45℃,n(3,4,5-三甲氧基苯乙酮)∶n(NBS)=1∶2时,产率为45.7%,因此筛选该条件为最优反应条件。化合物结构经核磁共振氢谱表证。     

溴代二苯酮与丙腈负离子的光诱导加成反应

芳香卤代物芳环上的卤原子在光诱导或电引发下可通过自由基链式亲核取代反应(S_(RN)|)而被有机负离子所取代。 我们以3-溴苯基-苯基-甲酮为底物,在丙腈碳负离子存在下进行光照,结果芳酮环上的溴原子未发生 S_(RN)|取代,而是在羰基上发生了光诱导加成反应,生成了未见文献报道的新化合物1-苯基-1-(3-溴苯基)-2-氰基丙醇-1(I)     

肟菌酯关键中间体的合成

以邻甲基苯乙酮为原料,依次经相转移催化下的高锰酸钾碱性氧化、甲醇酯化、甲氧胺盐酸盐肟化和N-溴代丁二酰亚胺(NBS)溴化后,得到制备肟菌酯的关键中间体——(E)-2-(2'-溴甲基苯基)-2-羰基乙酸甲酯-O-甲基酮肟。产品结构经熔点和1HNMR表征。通过优化反应条件,总收率可达52%。     

肟菌酯关键中间体的合成研究

以邻甲基苯乙酮为原料,依次经相转移催化下的高锰酸钾碱性氧化、甲醇酯化、甲氧胺盐酸盐肟化和N-溴代丁二酰亚胺（NBS）溴化后,得到制备肟菌酯的关键中间体——(E)-2-(2'-溴甲基苯基)-2-羰基乙酸甲酯-O-甲基酮肟。产品结构经熔点和1H-NMR表征。通过优化反应条件,总收率可达52%。     

2-(溴甲基)烟腈的合成研究

以2-甲基烟腈为原料,NBS为溴代试剂,BPO为引发剂,在四氯化碳溶液中发生自由基溴代反应得到2-(溴甲基)烟腈,产物结构通过~1H NMR和ESI-MS表征。并考察确定了该溴代反应的适宜条件为:NBS用量为n_(NBS)∶n_(2-甲基烟腈)=1.2∶1,反应溶剂为四氯化碳,反应温度60℃,反应时间7h,在该条件下,产物收率达到61.4%。     

1-溴-6-氰基-2-萘酚的合成

以2-萘酚(Ⅱ)为原料,经一锅两步反应制备6-溴-2-萘酚(Ⅳ),收率为89.0%;然后经氰化反应制备6-氰基-2-萘酚(Ⅴ),投料比n(CuCN)∶n(Ⅳ)=1.5∶1时收率为91.2%;最后分别用溴素和N-溴代丁二酰亚胺(NBS)两种不同的溴化试剂制备了1-溴-6-氰基-2-萘酚(Ⅰ)。以溴素为溴化试剂,乙酸为溶剂,n(Br2)∶n(Ⅴ)=1∶1,Ⅰ的收率为89.8%;该法成本较低,适合工业上大规模生产。以NBS为溴化试剂,乙腈为溶剂,n(NBS)∶n(Ⅴ)=1.00∶1.03,收率几乎定量(99.2%);该法条件温和,简单高效,可避免溴素易挥发和吸入毒性大的缺点,更适合实验室小规模合成。     

5,11,17,23-四溴-26,28-二甲氧基杯[4]芳烃的合成与表征

在室温下以丁酮为溶剂,26,28-二甲氧基杯[4]芳烃与N-溴代丁二酰亚胺(NBS)反应生成新化合物5,11,17,23-四溴-26,28-二甲氧基杯[4]芳烃,通过MS、1H NMR和13C NMR对其结构进行了表征.     

2-氟-5-溴硝基苯的合成

采用冰醋酸作为溶剂,以邻氟硝基苯为原料,N-溴代丁二酰亚胺(NBS)为溴代试剂,合成了2-氟-5-溴硝基苯。所得目标产物通过GC-MS定性、GC定量检测。结果表明,最佳反应条件为:n(邻氟硝基苯)∶n(NBS)=1∶1.05,以冰醋酸作溶剂,反应温度10℃,反应时间2 h,在该条件下2-氟-5-溴硝基苯的收率为98.6%,原料转化率100%。该反应条件温和,易于控制,重复性好。     

异香豆素类衍生物的卤化烷氧基化反应

以N-溴代丁二酰亚胺(NBS)、N-氯代丁二酰亚胺(NCS)分别为溴代、氯代试剂,醇类化合物作为反应原料及溶剂,实现了异香豆素类衍生物3,4-位的卤化烷氧基化反应.室温(25℃)下即可在3,4-位之间发生加成反应,合成具有潜在药理活性的异色满-1-酮类衍生物.对4-溴-3-甲氧基-3-苯基异色满-1-酮(Ⅳa)的合成反...     

四-(3,4-二甲氧基苯基)硫代双烯合镍的合成与光谱性能

以中间体二-(3,4-二甲氧基苯基)乙二酮为原料,经过P2S5硫化、镍络合,合成了四-(3,4-二甲氧基苯基)硫代双烯镍络合物近红外吸收染料.利用IR和1HNMR表征了最终产物硫代双烯合镍的结构.考察了四-(3,4-二甲氧基苯基)硫代双烯合镍在不同溶剂中的最大吸收波长及其光、热稳定性.     

Long-chain phenols: XX. Synthesis of oxidative degradation products from the methylated component phenols ofAnacardium occidentale and other phenolic lipids: Confirmation of the structure of the parent phenols and of a related material

A general procedure for the determination of the first double bond position in the side-chain of a phenolic lipid has been investigated and, in the first place, the phenols of natural cashew nut-shell liquid (Anacardium occidentale) have been examined. An improved oxidative degradation procedure has been applied consisting of methylation by the phase transfer procedure, hydroxylation with performic acid and oxidation of the mixture of vicinal diols with periodic acid (Malaprade reaction) followed by reduction of the aldehyde fragments with sodium borohydride. The aromatic moieties from the 15∶1, 15∶2 and 15∶3 constituents of cardanol methyl ether, cardol dimethyl ether and dimethyl anacardate were shown to be 8-(3-methoxyphenyl)octan-1-ol, 8-(3,5-dimethoxyphenyl)octan-1-ol and 6-(8-hydroxyocyl)salicylate methyl ether, respectively. The first two octanols were identical to synthetic materials, thus confirming the 8-position for the first double bond in the side-chain of cardanol methyl ether and cardol dimethyl ether constituents. Methyl 6-(8-hydroxyoctyl)salicylate relationship in a series of synthetic reference materials of log (retention time) to the methylene chain length. The synthetic acids 8-(3-methoxyphenyl)octanoic acid, 8-(3,5-dimethoxyphenyl)octanoic acid and 6-(7-carboxyheptyl)salicylic acid methyl ether have been obtained pure for the first time and correspond to the oxidation products of the aromatic aldehyde fragments from the Malaprade reaction stage. The unsaturation in peladjauol, 17∶1-bishomocardanol methyl ether, fromPentaspadon officinalis was confirmed to be at the 8-position by the identity of the anilides of synthetic 8-(3-methoxyphenyl) octanoic acid and of the oxidative degradation product. For part XIX, see ref. 1.     

Revisiting the Mechanism of β-O-4 Bond Cleavage During Acidolysis of Lignin. Part 3: Search for the Rate-Determining Step of a Non-Phenolic C6-C3 Type Model Compound

Abstract

The rate-determining step of a C₆-C₃ dimeric non-phenolic β-O-4 type lignin model compound, 2-(2-methoxyphenoxy)-1-(3,4-dimethoxyphenyl)propane-1,3-diol (veratrylglycerol-β-guaiacyl ether, VG), was evaluated under acidolysis conditions (0.2 mol/l HBr in 82% aqueous 1,4-dioxane at 85°C) by comparing the disappearances between VG and the corresponding compound labeled at the β-position of VG, 2-(2-methoxyphenoxy)-1-(3,4-dimethoxyphenyl)(2–²H)propane-1,3-diol. The disappearance of VG occurred more rapidly than that of the latter compound, and a primary kinetic isotope effect was clearly observed. This result indicates that the C-H bond at the β-position of VG is broken in the rate-determining step. Two possible mechanisms are presented as the rate-determining step: (1) A base abstracts the β-proton of a benzyl cation-type intermediate produced from VG affording an enol ether compound, 2-(2-methoxyphenoxy)-3-(3,4-dimethoxyphenyl)prop-2-en-1-ol; (2) The hydride transfers from the β- to the α-position of the benzyl cation. It was confirmed that both mechanisms certainly exist and that the latter seems to contribute more than has generally been considered.     

Revisiting the Mechanism of β-O-4 Bond Cleavage During Acidolysis of Lignin. Part 6: A Review

ABSTRACT

This paper reviews our results on the acidolysis of dimeric non-phenolic β-O-4-type lignin model compounds in aqueous 82% 1,4-dioxane containing an acid at 85°C. It was shown that the mechanism of a C₆-C₂-type model compound, 2-(2-methoxyphenoxy)-1-(3,4-dimethoxyphenyl)ethanol IX, is fairly different from that of a C₆-C₃ analogue, 2-(2-methoxyphenoxy)-1-(3,4-dimethoxyphenyl)propane-1,3-diol XX, suggesting the significance of the presence of the γ-hydroxymethyl group. It was confirmed that the hydride transfer mechanism exists as a reaction route of the benzyl-cation-type intermediates derived from both compounds, and the contribution of this mechanism is greater than expected in the acidolysis of compound XX. An enol ether compound, 2-(2-methoxyphenoxy)-3-(3,4-dimethoxyphenyl)prop-2-en-1-ol, was first detected in the acidolysis of compound XX using the DBr/D₂O/1,4-dioxane system. It was confirmed in the acidolysis of compound XX using HBr that the mechanism is different from that in the system using either HCl or H₂SO₄ and an unknown mechanism contributes to the reaction. This unknown mechanism surprisingly contributed more with decreasing concentration of HBr or Br^?, provided that Br^? still existed in the system.     

非达司他中间体的酶法拆分

(2S)-6-氟-3,4-二氢-4-氧代-2H-1-苯并吡喃-2-羧酸是合成非达司他(一种口服醛糖还原酶抑制剂)关键中间体。该研究使用脂肪酶Novozym 435,对(±)-6-氟-3,4-二氢-4-氧代-2H-1-苯并吡喃-2-羧酸甲酯进行拆分,并对拆分反应条件进行了优化,确定了拆分的最适反应条件:乙腈-水溶液为溶剂,V(水)∶V(乙腈)=1∶4,m(酶)∶m(底物)=1∶10,在pH=7.0,温度40℃,时间为6 h条件下,得到的(2S)-6-氟-3,4-二氢-4-氧代-2H-1-苯并吡喃-2-羧酸的总收率为32.5%,对映体过量值为92.1%,为非达司他的制备提供了一条可行途径。     

Separation of Penicillin G from Fermentation Broth Using N,N-Dioctyloctan-1-amine Extractant in Different Diluents

The extraction of penicillin G was investigated using N,N-Dioctyloctan-1-amine (TOA) with different diluents having distinct functional groups. Nine diluents were used in the study, namely, octan-1-ol, nonan-1-ol, isoamyl alcohol, ethyl ethanoate, propyl ethanoate, methyl iso butyl ketone(MIBK), octan-2-one, octane, and decane. The measurements were performed at a temperature of 298.2 K. The experimental results of batch extractions were used to calculate distribution coefficients (K_D), loading factors (Z), and extraction efficiency (E). The highest distribution coefficient (K_D = 5.79) was obtained with isoamyl alcohol, and its extraction efficiency was 85.27%. Further, the highest loading factor was reached to a value of 0.130 at 0.374 mol.kg^?1 amine concentration. Overloading was not observed at any amine concentration. Solvatochromic model (Linear solvation Energy Relationship (LSER)) for data which obtained from alcohols experiments gives the good results as near as same to experimental results. Suitability of data between experiments and model predictions have been tested with root main square deviation (RMSD) with 0.99.     

芳基取代丙烯腈为骨架的芪类化合物的合成

对合成结构较简单的4种以芳基取代丙烯腈为骨架的芪类化合物的常用合成方法进行了研究。以取代苯甲醛和取代苯乙腈为原料,在氮气保护、甲醇钠作催化剂等条件下,通过一步缩合反应,高收率得到(Z)-2-(3,4-二甲氧苯基)-3-(4-甲氧苯基)丙烯腈(Ⅰ)、(Z)-2-(3,4-二甲氧苯基)-3-(3,4-二甲氧苯基)丙烯腈(Ⅱ)、(Z)-2-(3,4-二甲氧苯基)-3-(4-二甲氨基苯基)丙烯腈(Ⅲ)、(Z)-3-(3,5-二甲氧苯基)-2-(4-甲氧苯基)丙烯腈(Ⅳ),实测收率分别为98.3%、96.0%、83.4%及88.8%。     

3-（2-羟基-4,5-二甲氧基苯基）丙酸钠的合成

丹参素有良好的药效,它的生物活性可能跟苯基乳酸结构有关,本论文以3,4-二甲氧基苯丙酸为原料,经溴代、水解反应合成了丹参素类似物3-（2-羟基-4,5-二甲氧基苯基）丙酸钠。     

硅胶负载硫酸(SSA)催化合成不对称芳基硫醚类化合物及其抗真菌活性和分子对接研究

通过固载催化剂硅胶硫酸(SSA)催化苯硫酚、芳香醛和5,5-二甲基-1,3-环己二酮进行多组分反应得到不对称芳基硫醚类化合物3-羟基-5,5-二甲基-2-[(1-苯硫基-1-苯基)]甲基-2-环己烯酮,SSA催化使反应产率更高且催化剂可重复使用。通过对催化剂量、温度和投料物质的量比进行优化得到了最佳反应条件。目标化合物结构通过IR、~1HNMR、~(13)CNMR和HR-MS进行确证,初步生物活性测试表明部分化合物具有抗新生隐球菌和白色念珠菌的活性。同时,对3-羟基-5,5-二甲基-2-[1-(2-氟苯硫基-1-苯基)]甲基-2-环己烯酮和白色念珠菌的N-肉豆蔻酰基转移酶(CaNMT)进行了分子对接研究。     

含氰基二元芳胺固化的酞菁预聚物的合成及表征

以亲核取代反应合成了3种酞菁单体(2,2′-二[4-(3,4-二氰基苯氧基)]丙烷(BAPh)、4,4′-二(3,4-二氰基苯氧基)联苯(BPh)、4,4′-二(3,4-二氰基苯氧基)甲烷(BFPh))和1种含有氰基的高熔点二元芳胺2,6-二(4-氨基苯氧基)苯甲腈(APBN)。通过核磁共振氢谱(1H-NMR)、傅里叶变换红外光谱(FT-IR)、示差扫描量热仪(DSC)和热重分析(TGA)对合成的化合物的化学结构,芳胺和酞菁单体的热聚合行为,不同固化时间预聚物的热性能进行了研究。结果表明,BAPh/APBN和BFPh/APBN体系分别具有宽达101℃与107℃的加工窗口。BFPh型预聚物(固化1 h)比其他2种预聚物具有更高的初始分解温度(390℃下失重5%)、高温残炭率(800℃下61.7%)和固化效率。