磷钨酸在吲哚与磺酰亚胺Friedel-Crafts反应中的应用

以磷钨酸为催化剂,成功催化了吲哚与磺酰亚胺的Friedel-Crafts反应,并合成了一系列双吲哚甲烷衍生物.研究结果显示,10 mol%磷钨酸能够很好地催化此反应,收率达到97%.所合成的双吲哚甲烷衍生物的结构经核磁共振谱和X射线单晶衍射确定.     

2-溴-3-(1H-吲哚-3)-N-甲基马来酰亚胺的合成

以琥珀酰亚胺为起始原料,经过溴化、甲基化后再与吲哚溴化镁加成反应合成了2-溴-3-(1H-吲哚-3)-N-甲基马来酰亚胺,总收率44.8%,其结构经1H NMR和IR确证.     

吲哚碳菁染料的合成及其光谱特性的研究

将(未)确定的1-(3'-磺酸丙基)2,3,3-三甲基吲哚啉内盐与原乙酸三乙酯在吡啶或酸酐中回流合成了五个氮原子上带有磺酸丙基的取代吲哚碳菁染料. 这些染料和杂环氮原子上带有烷基取代的吲哚碳菁相比, 它们具有较高的熔点, 在极性溶剂中具有较高的溶解度. 这些染料的最大吸收值在540～580nm之间, 并具有较高的消光系数(1～2×10^5L·mol·cm^-^1) .     

空气条件下温和高效催化N-吡啶吲哚啉的氧化脱氢

报道了空气条件下温和高效的N-羟基邻苯二甲酰亚胺和铜共同催化N-吡啶吲哚啉的氧化脱氢反应.已知的N-吡啶吲哚啉的氧化过程只能在过量强氧化剂2,3-二氯-5,6-二氰对苯醌存在下实现,该反应以空气作为单一的氧化剂,具有绿色、安全、低成本以及操作简便等优点,为N-吡啶吲哚啉类化合物氧化生成相应吲哚衍生物提供了一条新的绿色途径.     

光致变色6’-醛基螺吲■啉苯并吡喃的合成

6’-或8’-醛基螺吲哚啉苯并吡喃具有光致变色性质,加上该醛基又可与氨基、活泼甲基化合物以及Wittig试剂反应形成更有用的含C=N或C=C的化合物,因此,研究其合成     

有机磷酸催化合成双吲哚烷烃衍生物

以联萘二酚衍生的有机磷酸为催化剂,催化吲哚和羰基化合物的亲电取代反应,合成了一系列双吲哚衍生物,收率64%～95%,其结构经1H NMR,13C NMR和HR-MS确证。     

空气条件下温和高效催化N-吡啶吲哚啉的氧化脱氢（英文）

报道了空气条件下温和高效的N-羟基邻苯二甲酰亚胺和铜共同催化N-吡啶吲哚啉的氧化脱氢反应.已知的N-吡啶吲哚啉的氧化过程只能在过量强氧化剂2,3-二氯-5,6-二氰对苯醌存在下实现,该反应以空气作为单一的氧化剂,具有绿色、安全、低成本以及操作简便等优点,为N-吡啶吲哚啉类化合物氧化生成相应吲哚衍生物提供了一条新的绿色途径.     

手性磷酸催化合成多取代吡咯并[1,2-a]吲哚

以联萘二酚骨架的手性磷酸催化吲哚苄基醇和3-吲哚丙烯酸酯发生环加成反应,产生三个连续的手性中心.当使用3,3'-位被α-萘取代的联萘二酚骨架手性磷酸为催化剂时,反应的效果最佳,产率最高达91%以上,非对映选择性为9∶1~20∶1,对映选择性为62%~92%.     

新型萘酰亚胺衍生物的合成

N-(N’,N’-二甲基氨基乙基)-4-硝基-1,8-萘酰亚胺和2,3-二甲基苯并噻唑碘化盐在痕量水存在下经亲核取代反应合成了一个新型的萘酰亚胺衍生物——N-(N’,N’-二甲基氨基乙基)-4-[2-(2,3-二氢-2,3-二甲基苯并噻唑)氧基]-1,8-萘酰亚胺,其结构经1H NMR,13C NMR和ESI-MS表征。并对反应机理进行了初步研究。     

2-取代吲哚的染料敏化光氧化反应

2-苯基吲哚 (1a) 在甲醇中的染料敏化光氧化反应给出2-苯基-2-(2'-苯基-3'-吲哚基)二氢吲哚-3-酮 (2a) 和2-甲氧基-2-苯基二氢吲哚-3-酮 (4a), 相应N-甲基取代产物由1-甲基-2-苯基吲哚 (1b) 的类似反应获得。发现反应产物分布随吲哚 (1) 的浓度和介质酸度的变化而变化。对反应机理进行了推测, 其中当1a的反应在乙腈中进行时, 分离到了相应的反应中间体: 2-苯基-3H-吲哚-3-酮 (3a)。     

Synthesis of the cycloheptannelated indole fragment of dragmacidin E

Synthesis of the pivotal cycloheptannelated indole fragment of indole alkaloid dragmacidin E is achieved. The synthesis features a Pd-catalyzed indole synthesis reaction for the preparation of 3,7-disubstituted indole, a regioselective intramolecular Friedel–Crafts reaction for the construction of the 3,4-bridged cycloheptannelated indole skeleton, and a coupling reaction of vinyl triflate with diorganocuprate.     

Platinum-catalyzed multistep reactions of indoles with alkynyl alcohols

PtCl2 effectively catalyzes the multistep reaction of N-methyl indole (1 a) with pent-3-yn-1-ol (2 a) in THF at room temperature for 2 h to give indole derivative 3 a, which contains a five-membered cyclic ether group at C3 in 93% yield. Under similar reaction conditions, various substituted N-methyl indoles 1 b-h and indole (1 i) reacted efficiently with 2 a to afford the corresponding indole derivatives 3 b-h and 3 i in 48-91 and 72% yields. The results showed that N-methyl indoles with electron-donating substituents were more reactive affording higher product yields than those with electron-withdrawing groups. Likewise, various substituted but-3-yn-1-ols 2 b-e and other longer chain alkynyl alcohols 2 f-i also underwent a cyclization-addition reaction with N-methyl indole (1 a) to provide the corresponding cyclization-addition products 3 j-m and 3 a, 3 j, and 3 n-o in good to excellent yields. The present platinum-catalyzed cyclization-addition reaction can be further extended into N-methyl pyrrole. Mechanistically, the catalytic reaction proceeds by an intramolecular hydroalkoxylation of alkynyl alcohol to afford cyclic enol ether followed by the addition of the C--H bond of indole to the unsaturated moiety of cyclic enol ether providing the final product. Experimental evidence to support this proposed mechanism is provided.     

Indole synthesis by controlled carbolithiation of o-aminostyrenes

An effective synthesis of the functionalized indole ring system has been developed from substituted o-aminostyrene starting material. Our methodology involves a novel cascade reaction sequence of alkyllithium addition to the styrene double bond and subsequent trapping of the intermediate organolithium with a suitable electrophile, followed by an in situ ring closure and dehydration to generate the indole ring. This new reaction sequence allows for the introduction of molecular diversity at all positions on the indole scaffold. The procedure was shown to be successful with a range of both C and N substituents on the o-aminostyrenes. The reaction sequence was tolerant to the reactivity range of alkyllithiums such as tert-, sec-, and n-butyllithium. The electrophiles used were DMF, which generated indole products with C-2 unsubstituted, and nitriles, which incorporated the nitrile substituent at C-2. The o-aminostyrene starting materials were generated by a Pd-catalyzed cross-coupling reaction of a vinyl boronic acid equivalent with the readily available substituted o-bromoanilines.     

A study of the reaction of N-chlorosuccinimide with indoles and its analytical application

The reaction of N-chlorosuccinimide with indole and few of its derivatives in acid medium has been studied. The purified products have been identified by TLC, elemental analysis and infrared studies, and a reaction mechanism is proposed on the basis of the results. The reaction proceeds smoothly and consistently, and can be used for microdetennination of indole and its derivatives.     

NiWS/γ-Al2O3催化剂上吲哚加氢脱氮反应:H2S和喹啉的影响

在连续固定床微反装置上考察了吲哚（IND）和1,2-二氢吲哚（HIN）在NiWS/γ-Al₂O₃催化剂上加氢脱氮（HDN）的反应以及 H₂S和喹啉（Q）对其加氢脱氮反应的影响。结果表明,碱性含氮化合物HIN较吲哚对其自身的加氢脱氮反应抑制作用更为明显。H₂S能够促进HIN的C（sp³）－N断裂,但抑制了邻乙基苯胺（OEA）的 C（sp²）－N断裂;同时吲哚加氢反应途径也受到了抑制。喹啉的添加严重降低了吲哚加氢脱氮反应的转化率和脱氮率;喹啉对吲哚加氢反应和C－N键断裂反应均产生明显的抑制作用。喹啉的抑制作用主要源于喹啉及其中间产物1,2,3,4-四氢喹啉（THQ1）和5,6,7,8 -四氢喹啉（THQ5）与吲哚及其中间产物的竞争吸附。     

Enzymatic formation of indole-containing unnatural cyclic polyprenoids by bacterial squalene:hopene cyclase

[reaction: see text] Two indole-containing substrate analogues, in which a C20 isoprene unit is connected to indole (3-(geranylgeranyl)indole and 3-(farnesyldimethylallyl)indole), were synthesized and tested for enzymatic cyclization by squalene:hopene cyclase from Alicyclobacillus acidocaldarius. Interestingly, 3-(geranylgeranyl)indole was not a substrate for the bacterial squalene cyclase, while 3-(farnesyldimethylallyl)indole was efficiently converted to a 2:1 mixture of unnatural novel products.     

LUMIFLAVIN-SENSITIZED PHOTOOXYGENATION OF INDOLE

Abstract— The lumiflavin-sensitized photooxygenation of indole in aqueous solutions has been investigated by means of steady light photolysis and flash photolysis. The semiquinone of lumiflavin and the half-oxidized radical of indole were formed by the reaction between triplet lumiflavin and indole (3.7 times 10⁹ M ^-1 s^-1). The semiquinone anion radical of lumiflavin reacted with oxygen to form superoxide radical. The triplet state of lumiflavin also reacted with oxygen forming singlet oxygen, ¹O₂. But the reaction between ¹O₂ and indole (7 times 10⁷ M^_l s^_1; estimated from steady light photolysis using Rose Bengal as a sensitizer) was far less efficient than the reaction between indole and triplet lumiflavin. The quantum yield of the lumiflavin-sensitized photooxygenation of dilute indole via radical processes was much higher than that via ¹O₂ processes, though appreciable ¹O₂ was formed.     

The first method for protection-deprotection of the indole 2,3-pi bond

[reaction: see text] The scope and generality of a new reaction of indoles with MTAD is discussed. In most cases the ene-type reaction proceeds within seconds or minutes at 0 degrees C to provide the urazole adducts in high yield. This reaction provides the first method for protecting the indole 2,3-double bond since the urazole adducts can be reconverted to the starting indole (retro-ene) simply by heating.     

Unexpected formation of fluorine-containing tetrahydrocarbazole during the reaction of indole, paraformaldehyde, and fluorine-containing β-ketoesters

A surprise and mild method to prepare fluorine-containing indole derivatives through a one-pot three-component condensation reaction sequence is presented. To our surprise, during the reaction of preparation of fluorine-containing indole derivatives, unexpected formation of fluorine-containing tetrahydrocarbazole was found. Moreover, this method has been demonstrated in the preparation of functionalized polycyclic indole derivatives in a straightforward and atom-economical manner.     

Cascade Multicomponent Synthesis of Indoles,Pyrazoles, and Pyridazinones by Functionalization of Alkenes

The development of multicomponent reactions for indole synthesis is demanding and has hardly been explored. The present study describes the development of a novel multicomponent, cascade approach for indole synthesis. Various substituted indole derivatives were obtained from simple reagents, such as unfunctionalized alkenes, diazonium salts, and sodium triflinate, by using an established straightforward and regioselective method. The method is based on the radical trifluoromethylation of alkenes as an entry into Fischer indole synthesis. Besides indole synthesis, the application of the multicomponent cascade reaction to the synthesis of pyrazoles and pyridazinones is described.