醛类与1,2-二(对甲苯胺基)乙烷作用的研究Ⅰ.

1.用1,2-二(对甲苯胺基)乙烷与醛类缩合而得1,3-二(对甲苯基)-2-烃基四氢咪唑,在反应的专属性,缩合手续,产率及产物的熔点范围方面似均较前人用1,2-双苄胺基乙烷,1,2-二(对甲氧苄胺基)乙烷或1,2-二(对氯苄胺基)乙烷为佳. 2.改进1,2-二(对甲苯胺基)乙烷的合成方法,使产量提高,并消除副反应. 3.曾制备二十四种新的1,3-二(对甲苯基)-2-烃基四氢咪唑类化合物,和三种1,2-二(对甲苯胺基)乙烷的衍生物. 4.1,3-二(对甲苯基)-2-邻硝基苯四氢咪唑可用稀盐酸分解为相应的邻硝基苯甲醛和1,2-二(对甲苯胺基)乙烷的二盐酸盐,其反应几为定量.     

二氮陆环衍生物Ⅲ.——α,ω-双(1-取代基-4-二氮陆环基)烷类盐酸盐及1,2-双(1’-取代基-4’-二氮陆环基乙氧基)乙烷盐酸盐的合成

本文报告两类二氮陆圜衍生物:(α,ω-双(1-取代基-4-二氮陆圜基)烷类盐酸盐,及l,2-双(1’-取代基-4’-二氮陆圜基乙氧基)乙烷盐酸盐)的制备。α,ω-双(1-乙氧碳酰基-4-二氮陆圜基)烷类、及α,ω-双(1-二乙氨基碳酰基-4-二氮陆圜基)烷类,可由1-取代基二氮陆圜与相当的α,ω-二溴烷,经碳酸氢钠作用制成。 1.2-双(1’-乙氧碳酰基-4’-二氮陆圜基乙氧基)乙烷、及1,2-双(1’-二乙氨基碳酰基-4’-二氮陆圜基乙氧基)乙烷,可由1,2-双(β-氯乙氧基)乙烷先和碘化钠作用,制成碘化物,然后再与相当的1-取代基二氮陆圜经碳酸氢钠作用制成。上述两类化合物的1-甲基二氮陆圜衍生物,均系由过量的1-甲基二氮陆圜,与相当的α,ω-二溴烷或1,2-双(β-氯乙氧基)乙烷在乾燥苯中作用制成。     

碘化钾在1,2-双(二溴甲基)苯及4位取代衍生物与反丁烯二腈反应中的作用

1,2-双(二溴甲基)苯及4位取代衍生物与反丁烯二腈在N,N-二甲基甲酰胺中反应12 h没有新的产物生成,在同样的条件下,加入碘化钾可使反应发生,主产物是2,3-二氰基萘及其6位取代衍生物,它的产率随加入的碘化钾的量不同而不同.当碘化钾的加入量相当于1,2-双(二溴甲基)苯及4位取代衍生物分子中溴的摩尔数,则1,2-双(二溴甲基)苯及其4位取代衍生物与反丁烯二腈基本作用完毕,反应产物主要是2,3-二氰基萘及其6位取代衍生物,产率87.1%.这个实验事实表明,碘化钾的作用机制不是传统意义上的催化剂而是一个反应试剂.据此,提出了上述反应的机理.     

9-(2-溴乙基)腺嘌呤合成工艺研究

研究了用腺嘌呤和1,2-二溴乙烷合成9-(2-溴乙基)腺嘌呤的方法.讨论了物料配比、反应时间、碳酸钾用量等因素对反应的影响.确定了合成9-(2-溴乙基)腺嘌呤的最佳反应条件,在选择的试验条件下产率为81.0%.     

联1,2-二氢咪唑并苯并咪唑的水相绿色合成

1,2-二氢咪唑并苯并咪唑衍生物具有杀菌等生物活性。为了进一步研究其抗真菌活性,于室温下以2-氨甲基苯并咪唑与乙二醛在水中反应,高产率水相绿色合成了联1,2-二氢咪唑并苯并咪唑,产率达88.6%,进一步讨论了反应的机理。     

Ⅱ.3,4-二甲氧基苯乙胺衍生的若干化合物

β-(3,4-二甲氧基)苯乙胺与甲醛及甲酸在封管中热至125°,生成N,N-二甲基衍生物.2-溴-1-(3,4-二甲氧基)苯乙烷与二乙胺或六氢吡啶缩合则成相应N,N-二乙基衍生物或N-六氢吡啶衍生物.在无水碳酸钠作用下,N-甲基-β-(3,4-二甲氧基)苯乙胺经氯化苄、2-溴-1-苯乙烷或2-溴-1-(3,4-二甲氧基)苯乙烷烷化,分别生成相应N-甲基-N-芳烷基-β-(3,4-二甲氧基)苯乙胺.β-(3,4-二甲氧基)苯乙胺经乙酸酐或苯乙酰氯酰化后,再以五氧化二磷环化,并以锌粉及盐酸还原,分别制成1-甲基及1-苄基-6,7-二甲氧基-1,2,3,4-四氢异喹啉.以上制成的化合物均可认为是镇痛药延胡索素乙的裂环化合物,并已进行药理试验.     

1-烷基-2-甲基咪唑衍生物的高效简便合成

本文优化了溴乙烷与2-甲基咪唑的N-烷基化反应条件,并且高收率地合成了一系列具有抗菌活性的1-烷基-2-甲基咪唑衍生物。     

“一锅法”合成离子液体1-乙基-3-甲基咪唑醋酸盐

以1-甲基咪唑,溴乙烷和乙酸铅为原料,采用"一锅法"合成了离子液体1-乙基-3-甲基咪唑醋酸盐,产率87%,其结构经UV,IR和元素分析确证。优化反应条件为:1-甲基咪唑100 mmol,n(溴乙烷):n(1-甲基咪唑):n(乙酸铅)=3.6:2.0:1.0,于60℃反应20 h。     

水相中微波辅助合成咪唑并[1,2-α]吡啶衍生物的研究

开展了水相中硝基烯烃与氨基吡啶反应生成咪唑并[1,2-α]吡啶衍生物的微波辅助合成研究。结果表明:相同反应时间,在微波辅助条件下,生成咪唑并[1,2-α]吡啶衍生物的速率较常规加热条件下增大。一系列咪唑并[1,2-α]吡啶衍生物被高效的合成出来,最高产率达到85%。产物结构经~1H NMR,~(13)C NMR及MS得到确证。该方法具有产率高、操作简单、环境友好等优点。     

氯硝柳胺衍生物的合成与结构表征

由氯硝柳胺与1,2-二溴乙烷反应,得到2-(2-溴乙氧基)-5-氯-N-(2-氯-4-硝基苯基)苯甲酰胺,再与乙二醇、二乙二醇、三乙二醇分别反应,得到了三个氯硝柳胺衍生物,其结构由IR1、H NMR和高分辨质谱确证。     

Synthesis of trans-Disubstituted Alkenes by Cobalt-Catalyzed Reductive Coupling of Terminal Alkynes with Activated Alkenes

A cobalt-catalyzed reductive coupling of terminal alkynes, RC?CH, with activated alkenes, R'CH?CH(2) , in the presence of zinc and water to give functionalized trans-disubstituted alkenes, RCH?CHCH(2) CH(2) R', is described. A variety of aromatic terminal alkynes underwent reductive coupling with activated alkenes including enones, acrylates, acrylonitrile, and vinyl sulfones in the presence of a CoCl(2) /P(OMe)(3) /Zn catalyst system to afford 1,2-trans-disubstituted alkenes with high regio- and stereoselectivity. Similarly, aliphatic terminal alkynes also efficiently participated in the coupling reaction with acrylates, enones, and vinyl sulfone, in the presence of the CoCl(2) /P(OPh)(3) /Zn system providing a mixture of 1,2-trans- and 1,1-disubstituted functionalized terminal alkene products in high yields. The scope of the reaction was also extended by the coupling of 1,3-enynes and acetylene gas with alkenes. Furthermore, a phosphine-free cobalt-catalyzed reductive coupling of terminal alkynes with enones, affording 1,2-trans-disubstituted alkenes as the major products in a high regioisomeric ratio, is demonstrated. In the reactions, less expensive and air-stable cobalt complexes, a mild reducing agent (Zn) and a simple hydrogen source (water) were used. A possible reaction mechanism involving a cobaltacyclopentene as the key intermediate is proposed.     

Synthesis of trans‐Disubstituted Alkenes by Cobalt‐Catalyzed Reductive Coupling of Terminal Alkynes with Activated Alkenes

A cobalt‐catalyzed reductive coupling of terminal alkynes, RC?CH, with activated alkenes, R′CH?CH₂, in the presence of zinc and water to give functionalized trans‐disubstituted alkenes, RCH?CHCH₂CH₂R′, is described. A variety of aromatic terminal alkynes underwent reductive coupling with activated alkenes including enones, acrylates, acrylonitrile, and vinyl sulfones in the presence of a CoCl₂/P(OMe)₃/Zn catalyst system to afford 1,2‐trans‐disubstituted alkenes with high regio‐ and stereoselectivity. Similarly, aliphatic terminal alkynes also efficiently participated in the coupling reaction with acrylates, enones, and vinyl sulfone, in the presence of the CoCl₂/P(OPh)₃/Zn system providing a mixture of 1,2‐trans‐ and 1,1‐disubstituted functionalized terminal alkene products in high yields. The scope of the reaction was also extended by the coupling of 1,3‐enynes and acetylene gas with alkenes. Furthermore, a phosphine‐free cobalt‐catalyzed reductive coupling of terminal alkynes with enones, affording 1,2‐trans‐disubstituted alkenes as the major products in a high regioisomeric ratio, is demonstrated. In the reactions, less expensive and air‐stable cobalt complexes, a mild reducing agent (Zn) and a simple hydrogen source (water) were used. A possible reaction mechanism involving a cobaltacyclopentene as the key intermediate is proposed.     

A Sterically Tuned Directing Auxiliary Promotes Catalytic 1,2-Carbofluorination of Alkenyl Carbonyl Compounds**

The site-selective palladium-catalyzed three-component coupling of unactivated alkenyl carbonyl compounds, aryl- or alkenylboronic acids, and N-fluorobenzenesulfonimide is described herein. Tuning of the steric environment on the bidentate directing auxiliary enhances regioselectivity and facilitates challenging C(sp³)−F reductive elimination from a Pd^IV intermediate to afford 1,2-carbofluorination products in moderate to good yields.     

铝-碱金属氟化物在超声辐射下于水中诱发的芳香醛还原偶联

超声辐射下, 铝粉在氟化钾或氟化钠的水溶液中, 可使芳香醛快速还原或偶联, 生成相应的双分子还原偶联产物和少量单分子还原产物, 其中还原偶联产物邻二醇的收率达15%～82%.     

Vanadium-catalyzed pinacol coupling reaction in water

A catalytic pinacol coupling using water as a solvent was performed by a catalytic amount of vanadium(III) chloride and metallic Al as a co-reductant. A combination forms a binary catalytic system, being in sharp contrast to the reaction in organic solvent, which requires a chlorosilane as an additive. Various aromatic aldehydes underwent the reductive coupling to give the corresponding 1,2-diols in moderate to good yields.     

Zirconocene Dichloride–Catalyzed Pinacol Coupling of Aromatic Aldehydes and Ketones

The reductive coupling of aromatic aldehydes and ketones has been achieved using a catalytic amount of zirconocene dichloride in the presence of magnesium metal and chlorotrimethylsilane in THF at room temperature to afford the corresponding 1,2‐diols in good yields and diastereoselectivity.     

A New Method for the Synthesis of 1,2-bis(Pyrrol-2-yl)ethenes

1,2-Bis(2-pyrryl)ethenes were synthesized in high yields by the low-valent titanium mediated reductive coupling of pyrrole-2-carboxaldehydes. The reactions of pyrrole-2-carboxaldehyde under lowvalent titanium conditions were different from those of pyrrole-3-carbonyl compounds.     

Organocatalytic Enantiospecific Total Synthesis of Butenolides

Biologically important, chiral natural products of butenolides, (−)-blastmycinolactol, (+)-blastmycinone, (−)-NFX-2, (+)-antimycinone, lipid metabolites, (+)-ancepsenolide, (+)-homoancepsenolide, mosquito larvicidal butenolide and their analogues were synthesized in very good yields in a sequential one-pot manner by using an organocatalytic reductive coupling and palladium-mediated reductive deoxygenation or organocatalytic reductive coupling and silica-mediated reductive deamination as the key steps.     

二碘化钐作用下缺电子烯烃的还原偶联反应

室温下SmI2-HMPA-t-BuOH-THF体系能顺利地将丁烯二酸二酯还原偶联为1, 2, 3, 4-四烷氧基羰基丁烷, 同样条件下, 亚苄基氰乙酸乙酯,α-乙氧羰基肉桂酸乙酯, α-乙酰基肉桂酸乙酯和亚苄基丙二酸亚异丙酯等化合物也发生还原偶联反应得到相应的二聚体。     

Intermolecular Couplization and Cyclization of Chalcones Promoted by Samarium in DMF

Under mild and neutral conditions, reductive coupling–cyclization of chalcones was promoted by samarium metal with an activator in DMF to afford products in good to excellent yields. The reaction is regioselective over the competitive carbon–carbon double-bond reduction and stereocontrolled.