2-苯氧(硫)甲基-6,7-亚甲二氧-3-喹啉酸乙酯及其衍生物的合成

6-氨基胡椒醛与乙酰乙酸乙酯在碱的催化下, 缩合产物与NBS发生溴代反应, 生成2-溴甲基-6,7-亚甲二氧基-3-喹啉酸乙酯,产物与苯酚,取代苯酚, 苯硫酚, 取代苯硫酚发生Williamson取代反应, 高分辨地得到一系列喹啉吩醚衍生物, 苯酚和硫酚上的吸电子基团有利于增强亲核能力,有利于Williamson反应.     

“一锅法”合成2-[(2,4-二叔丁基苯氧基)甲基]-6,7-二氧戊环并[1,3-g]喹啉-3-羧酸(英文)

采用一锅法的合成方式有效地合成了2-(2,4-二叔丁基苯氧基)甲基-6,7-二氧戊环并[1,3-g]喹啉-3-羧酸,其特点是将威廉姆逊反应和碱水解这两步反应在"一锅里"进行.所得化合物的结构经IR、1 HNMR、MS和元素分析得以证实.     

芳亚甲基丙二腈和4-羟基喹啉-2-酮反应的研究

以芳亚甲基丙二腈和4-羟基喹啉-2-酮为原料,在六氢吡啶催化下以乙醇为溶剂,80℃合成了一系列新的2-氨基-3-氰基-4-芳基5,6-二氢化-4H-吡喃并[3,2-c]喹啉-5-酮衍生物,反应条件温和,产率较高,并通过单晶X射线衍射分析确证产物的结构.     

叔丁基杯[6]芳烃的去叔丁基反应

报道了以对叔丁基杯[6]芳烃为原料,室温时,在三氯化铝催化下选择性脱去叔丁基的工艺.探讨了在合成去叔丁基杯[6]芳烃实验中催化剂用量对反应结果的影响,并对反应机理进行了讨论.结果表明,当n(AlCl3)∶n(p-tert-calix[6]arene)=8~9.5∶1时,分离得到了两种去叔丁基杯[6]芳烃:5-叔丁基-37,38,39,40,41,42-六羟基杯[6]芳烃和37,38,39,40,41,42-六羟基杯[6]芳烃,当n(AlCl3)∶n(p-tert-calix[6]arene)=10.5∶1时,得到37,38,39,40,41,42-六羟基杯[6]芳烃,产率90.8%.     

2-(5,7-二氯/二溴-8-喹啉氧甲基)-4-苯基喹啉-3-羧酸乙酯的便捷合成(英文)

在K2CO3作为碱、乙腈作为溶剂的条件下,将2-氯甲基-4-苯基喹啉-3-羧酸乙酯(3)分别与5,7-二氯-8-羟基喹啉(4a)和5,7-二溴-8-羟基喹啉(4b)发生Williamson反应,以高收率得到结构新颖的二氯或二溴取代的双喹啉类目标化合物2-(5,7-二氯/二溴-8-喹啉氧甲基)-4-苯基喹啉-3-羧酸乙酯(2a,2b);其结构经波谱数据和元素分析证实.     

含4-苯基喹啉结构的双喹啉类衍生物的合成（英文）

2-氯甲基-4-苯基喹啉-3-羧酸乙酯(5)与8-羟基喹啉(6a-c)在乙醇钠为碱无水乙醇为溶剂的条件下进行威廉姆逊反应,合成了新颖有趣的含有4-苯基喹啉结构的双喹啉衍生物(4a-c)。随后,其3-位的酯基团在80%氢氧化钾乙醇溶液中发生水解反应得到相应的喹啉-3-羧酸(4d-f)。化合物4a-f的结构均已通过波谱数据和元素分析得以表征确认。     

2—甲基—3—喹啉酸乙酯衍生物的合成

本文报道由化合物(1)经缩合、水解等反应合成10种新化台物,反应式如下:     

通过异喹啉盐与环状1,3-二酮一锅合成二氢异喹啉-3-酮-1,4-桥环结构

异喹啉盐具有两个亲电位点, 用它与双亲核试剂发生去芳构化/环化反应, 是高效构建异喹啉桥环结构的有效策略. 然而, 这一策略主要集中在1,3-桥环结构的合成. 最近利用异喹啉盐与4-羟基香豆素反应, 首次实现了二氢异喹 啉-3-酮-1,4-桥环的合成. 但是, 当用环状1,3-二酮代替4-羟基香豆素反应时, 意外地得到了异喹啉-1,3,4(2H)-三酮. 利用高分辨质谱分析发现, 这一意外转化是由于环状1,3-二酮发生O-亲核取代后, 消除2-溴-1,3-环状二酮, 得到4-溴异喹啉-3(2H)-酮. 该中间体发生两次连续水解/空气氧化后, 得到了异喹啉-1,3,4(2H)-三酮. 基于此机理的认识, 向反应体系中添加催化量的三氟甲烷磺酸后, 成功抑制了环状1,3-二酮的O-亲核取代反应, 顺利得到了二氢异喹啉-3-酮的1,4-桥环结构(33个反应实例). 反应条件温和, 提供了一种构建异喹啉1,4-桥环骨架的高效合成方法.     

N-苯基和N-乙氧羰基甲基磷异喹啉酮及其衍生物的合成

以邻炔基苯磷酰胺为原料经Pd(II)催化的环化反应、环化偶联反应和氯环化反应高收率合成了15个N-苯基和N-乙氧羰基甲基磷异喹啉酮及其4-烯丙基、4-氯衍生物, 它们的结构均经过1H NMR, 13C NMR, MS, IR及元素分析确证.     

3-甲基犬尿喹啉酸衍生物的合成

报道了六个具有潜在生物活性 3 甲基犬尿喹啉酸衍生物的合成 .它们以取代苯胺和 3 甲基 2 酮丁二酸二乙酯为起始原料 ,经加成脱水 ,环化而得到 .其中三个新的含氟化合物的结构分别经IR ,1 HNMR ,MS ,元素分析等表征     

De-tert-butylation of poly(N-tert-butyl-N-n-propylacrylamide): Stereochemical analysis at the triad level

The stereochemical analysis of polymers derived from N,N-disubstituted acrylamides is usually difficult. The diad tacticity can be determined from the ¹H nuclear magnetic resonance (NMR) signals of the main-chain methylene groups. However, the splitting because of the configurational sequences is poor, even in ¹³C NMR, which does not allow determination of the tacticity at the triad level. In contrast, the stereochemical analysis of polymers derived from N-monosubstituted acrylamides is easily conducted and the triad tacticity can be determined from the ¹³C signals of the main-chain methine groups. Thus, stereochemical analysis of N,N-disubstituted polymers should be able to be conducted if the polymers are transformed into N-monosubstituted polymers with retention of the configurational sequence. Poly(N-tert-butyl-N-n-propylacrylamide) was radically prepared, and de-tert-butylation was conducted by treatment with scandium triflate in a mixed solvent of CH₃CN and 1,4-dioxane at 50, 80, and 110°C. ¹H NMR analysis of the resulting polymers indicated quantitative conversion after 72 hr, regardless of the temperature. ¹³C NMR analysis of the transformed polymers confirmed that the configurational sequences were retained during the reaction. Thus, the triad stereochemical analysis of N,N-disubstituted polymers was successfully conducted by de-tert-butylation as a polymer reaction, followed by ¹³C NMR analysis of the transformed polymers.     

Synthesis and Cyclization of 8‐Formyl‐2‐(phenoxymethyl)quinoline‐3‐carboxylic Acids

A facile synthesis of a series of new quinoline‐8‐carbaldehyde compounds, namely 8‐formyl‐2‐(phenoxymethyl)quinoline‐3‐carboxylic acids ( 4a – 4h ) and 13‐oxo‐6,13‐dihydro[1]benzoxepino[3,4‐b]quinoline‐8‐carbaldehyde ( 5a – 5g ) is described, involving the one‐pot synthesis reaction of ethyl 2‐(chloromethyl)‐8‐formylquinoline‐3‐carboxylate ( 3 ) with substituted phenols followed by the intramolecular cyclization reaction via the treatment with polyphosphoric acid (PPA). Quinoline‐8‐carbaldehydes 4a – 4h and 5a – 5g are novel and their structures were supported by IR, ¹H NMR, ¹³C NMR, MS and elemental analysis.     

Synthesis of Asymmetric 4H-1, 3, 2-Benzodioxaphosphorin 2-Sulfides from Intramolecular Cyclization Reaction

Avarietyofbiologicalactivitiesofsome4H-l,3,2-benzodioxaphosphorin2-sulfideshavebeenreported,forexampletheinsecticideSalithionl.Thecyclicphosphonothionateshavebeenpreparedbyintermolecularcondensationofphosphorodichloridothioateswithsalicylalcoholoritsderivativesinthepresenceofabase=,andbyintramolecularcyclizationreactionofthesalicylalasthestartingmaterial3.However,theintramolecularcyclizationreactionofthe2-hydrobenzophenonesandstereochemicalstudieshavenotbeenreported.Wenowdescribeanewsynthesis…     

Synthesis and Reaction of 2-Mercapto-3-Arylpropanoic Acids

Abstract

Two synthetic pathways for the preparation of 2-mercapto-3-arylpropanoic acids were developed. First, by the reaction of arenediazonium bromides with acrylic esters in the presence of CuBr, alkyl (2-bromo-3-aryl)propanoates were formed. Their cyclization with thiourea produced 5-(R-benzyl)-2-imino-4-thiazolidinones, which yielded 3-aryl-2-mercaptopropanoic acids by alkaline hydrolysis. Second, direct Meerwein arylation of acrylates in the presence of S-nucleophile (NaSH) allowed isolation of 3-phenyl-2-mercaptopropanoic acid in 8% yield. Such acids were used for cyclization with cyanoguanidine and phenyl isothiocyanate yielding 1-[5-(R-benzyl)-4-oxo-1,3-thiazolidin-2-ylidene]guanidines and new 5-(R-benzyl)-3-phenyl-2-thioxo-1,3-thiazolidin-4-one (rhodanine) derivatives correspondingly.     

Intramolecular Cyclization of 4-Isocyanato-3-(2-naphthyl)-1-phenylpyrazole Under Friedel-Crafts Reaction Conditions

4-Isocyanato-3-(2-naphthyl)-1-phenylpyrazole cyclized under the influence of AlCl₃ to give 2H-benzo[h]pyrazolo[4,3-c]isoquinoline.     

Fe(0)催化三氯乙酸烯丙酯的环化反应研究

通过对Fe(O)催化烯烃自由基环化反应的研究，发现以Fe(O)为催化剂催化三氯 乙酸烯丙酯分子内自由基环化反应可以高化学选择性得到五元环内酯产物，反应中 不需加入配体。和大多数自由基反应一样，反应温度与催化剂用量对该反应的转化 率和产率有着很大的影响。     

Crystal Structure of Trans-2-Amino-3-Cyano-4-(3',4'-Methylenedioxyphenyl)-1-Phenyl-2-Cyclopentene-r-1-ol

1INTRODUCTIONIntheearlyseventiesthreegroupsofinvestigators('--"establishedthatlow--va-lenttitanium,preparedbythereactionofstrongreducingagentsontitaniumtrichlo-rideortitaniumtetrachlorideintetrahydrofuran,canabstractoxygenfromketonesoraldehydes,leadingtotheformationofolefins.Anincreasinginterestinthereac-tioninducedbylow--valenttitaniumreagentsisobservedandalargenumberoffunc-tionalgroupscanbereducedt4--6).However,thereactionoflow-valenttitaniumreagentwith4,4--dicyano--1,3--diaryl--l-butano…     

6-Endo Heck Cyclization of 3-(2-Iodophenoxy)methylbenzofurans: A Useful Approach to Pterocarpenes

Mitsunobu coupling of 3-hydroxymethylbenzofurans with o-iodophenols affords 3-(2-iodophenoxy)methylbenzofurans which under go a useful 6-endo Heck cyclization under Jeffery conditions to afford pterocarpene-type heterocycles. The unsubstituted parent pterocarpene thus prepared was readily converted to coumestan via subsequent PCC oxidation.

Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.     

2-叔丁基-4-氟-苯并氧杂卓并[3,4-b]喹啉并

以2-溴甲基-6,7-亚甲二氧基-3-喹啉酸乙酯(1) 为原料,经三步合成了2-叔丁基-4-氟-苯并氧杂卓并[3,4-b]喹啉并[9,11]二氧戊环-14(6H)-酮(4).其中,6-(2-氟-4-叔丁基-苯氧甲基)-[1,3]二氧戊环并[4,5-g]喹啉-7-羧酸是经一锅法合成的.它的分子内闭环反应是在Eaton's reagent(P2O5-CH3SO3H)的作用下,在较温和的条件下进行的.所得新化合物3和4的结构经IR、1H NMR和元素分析得以证实.