BF3·Et2O催化Pechmann反应一锅合成3-氨基-5,7-二羟基-4-甲基香豆素

3-氨基-5,7-二羟基-4-甲基香豆素（4）是一种新的重要有机合成中间体,可用于多种潜在生物活性物质的合成。本文将间苯三酚与2-乙酰氨基乙酰乙酸乙酯（2）在BF3.Et2O的催化作用下,经串联的Pechmann缩合反应和脱乙酰基反应一锅合成4。化合物2由乙酰乙酸乙酯经成肟、还原、酰化反应制得。中间体和目标物的结构均经1H NMR、13C NMR、MS表征。该方法具有原料廉价易得、步骤短、操作简便易控、反应条件温和、收率高的优点。     

3,3-二{2,2-二[4-(N,N-二取代氨基)苯基]乙烯基}-4,5,6,7-四氯-2-苯并[c]呋喃酮的合成

在对甲苯磷酸存在下,采用1,1-二[4-(N,N-二取代氨基)苯基]乙烯(3)和四氯苯酐在乙酸酐溶液中的缩合反应合成了3,3-二{2,2-二[4-(N,N-二取代氨基)苯基]乙烯基}-4,5,6,7-四氯-2-苯并[c]呋喃酮(4),产率89～93％。3由4,4＇-二(N,N-二取代氨基)二苯甲酮(1)与甲基碘化镁进行Grignard反应的产物经水解再脱水制得,产率85％～88.5％(以1为基准)。     

芳基喹啉取代螺二芴化合物的合成

2-溴联苯格式试剂与9-芴酮生成的叔醇中间体在酸性条件下环合形成螺二芴,再经Friedel-Crafts酰基化得到2-乙酰基螺二芴(3)和2,2-二乙酰基螺二芴(4);3或4与2-氨基二苯甲酮衍生物在酸催化下经过Friedlander缩合,制备了一系列具有荧光性的2-(4-取代苯基)喹啉-9,9'-螺二芴或2,2'-二(4-取代苯基)喹啉-9,9'-螺二芴,其结构经UV-vis,荧光光谱,1H NMR和元素分析表征.     

2-氰基-3,4-二氢喹唑啉衍生物的合成

邻硝基苯甲醛与取代苯胺(1)或取代苄胺(2)进行还原氨化反应得N-(2-硝基苄基)取代苯胺(3)或N-(2-硝基苄基)取代苄胺(4);将3或4的硝基还原为氨基生成关键中间体N-(2-氨基苄基)取代苯胺(5)或N-(2-氨基苄基)取代苄胺(6);5或6分别与4,5-二氯-1,2,3-二噻唑氯化物进行缩合反应,合成了一系列新的2-氰基-3,4-二氢喹唑啉类衍生物,收率36%~72%,其结构经1H NMR和HR-MS确证。     

N-(5-邻氯苯基-2-呋喃甲酰氨基)丙氨酰胺衍生物的合成和 生物活性测定

以5-邻氯苯基-2-呋喃甲酰氯和丙氨酸为起始原料, 通过非均相法得到N-(5-邻氯苯基-2-呋喃甲酰氨基)丙氨酸, 再与10种不同取代苯胺反应, 通过N,N’-二环己基碳二亚胺和4-二甲氨基吡啶(DCC/DMAP)偶合法设计合成了10个未见文献报道的N-(5-邻氯苯基-2-呋喃甲酰氨基)丙氨酰胺类衍生物4a～4j. 通过元素分析, 1H NMR, IR 和MS确定化合物的结构, 初步生物活性测试表明标题化合物具有一定的除草活性.     

苯甲酰氧基取代的2-吡喃酮的固相光二聚反应

以二苯甲酮为光敏化剂,C4-位苯甲酰氧基取代的6-甲基-2-吡喃酮(1)的固相光二聚反应穿过1的C3-C4双键高选择性地发生[2+2]环加成反应合成了anti头-头二聚物(2),其结构经1H NMR,FI-IR,MS和元素分析表征。反应机理利用WINMOPAC PM5方法推定。     

二苯乙烯衍生物的合成及抗肿瘤活性

以甲氧基取代的4’-氨基二苯乙烯与4-溴甲基-5-甲基-1,3-二氧杂环戊烯-2-酮为原料,通过亲核取代反应合成得到了4种新的二苯乙烯衍生物。这些化合物的结构经NMR、IR和元素分析确定。以HeLa、SMMC-7721、BGC-823和A549为受试细胞株,用MTT法测试了这4种化合物的抗肿瘤活性。测试结果表明,这些化合物具有一定的抗肿瘤活性。     

喹啉取代咔唑化合物的合成

以咔唑为原料,通过乙酰化反应合成了2-乙酰基咔唑(2)和3,6-二乙酰基咔唑(5);2和5分别与2-氨基二苯甲酮衍生物在酸催化下通过典型的Frledl(a)ender环化反应合成了一系列新的2-(4-取代苯基)喹啉咔唑和3,6-二(4-取代苯基)喹啉咔唑,其结构经1H NMR,IR和元素分析表征.     

4-二甲氨基吡啶催化的1,3-二酮与3-丁炔-2-酮的苯环化反应

在4-二甲氨基吡啶(DMAP)催化下, 1,3-二酮与3-丁炔-2-酮可以区域选择性地合成四取代的苯, 该方法具有反应条件温和和操作简单等优点, 产物的结构通过IR, 1H NMR, 13C NMR, HRMS确证.     

3,3-二{2,2-二[4-(N,N-二取代氨基)苯基]乙烯基}-4,5,6,7-四氯-2-苯并[c]呋喃酮的合成

在对甲苯磺酸存在下，采用1,1-二[4-(N,N-二取代氨基)苯基]乙烯(3)和四氯苯酐在乙酸酐溶液中的缩合反应合成了3,3-二{2,2-二[4-(N,N-二取代氨基)苯基]乙烯基}-4,5,6,7-四氯-2-苯并[c]呋喃酮(4)，产率89～93%。3由4,4'-二(N,N-二取代氨基)二苯甲酮(1)与甲基碘化镁进行Grignard反应的产物经水解再脱水制得，产率85%～88.5%(以1为基准)。     

Syntheses and characterization of oxygen/sulfur-bridged incomplete cubane-type clusters, [Mo3S4Tp3]+ and [Mo3OS3Tp3]+, and a mixed-metal cubane-type cluster, [Mo3FeS4ClTp3]. X-ray structures of [Mo3S4Tp3]Cl, [Mo3OS3Tp3]PF6, and [Mo3FeS4ClTp3

The reaction of [Mo3S4(H2O)9]4+ (1) with hydrotris(pyrazolyl)borate (Tp) ligands produced [Mo3S4Tp3]Cl x 4 H2O ([3]Cl x 4 H2O) in an excellent yield. An X-ray structure analysis of [3]Cl x 4 H2O revealed that each molybdenum atom bonded to the Tp ligand. We report four salts of 3, [3]Cl x 4 H2O, [3]tof x 2 H2O, [3]PF6 x H2O, and [3]BF4 x 2 H2O in this paper. The solubility and stability of the chloride salt in organic solvents differ completely from those of the other salts. We have also prepared a new compound, [Mo3OS3Tp3]PF6 x H2O ([4]PF6 x H2O), via the reaction of [Mo3OS3(H2O)9]4+ (2) with KTp in the presence of NH4PF6. All the molybdenum atoms bonded to Tp ligand. 1H NMR signals corresponding to nine protons bonded to three pyrazole rings in one Tp were observed in a spectrum (at 253 K) of [3]BF4 x 2 H2O. It shows that cluster 3 has a 3-fold rotation axis in CD2Cl2 solution. Twenty-one 1H NMR signals corresponding to twenty-seven protons bonded to nine pyrazole rings in three Tp ligands were observed in a spectrum (at 233 K) of [4]PF6 x H2O; obviously, 4 has no 3-fold rotation axis, in contrast to 3. The short CH...mu3S distance caused large upfield chemical shifts in the 1H NMR spectra of 3 and 4. The reaction of 3 with metallic iron in CH2Cl2 produced [Mo3FeS4XTp3] (X = Cl (5), Br (6)). X-ray structure analysis of 5 has revealed the existence of a cubane-type core Mo3FeS4. Complex 3 functions as a metal-complex ligand for preparing a novel mixed-metal complex even in nonaqueous solvents. The cyclic voltammogram of 5 shows two reversible one-electron couples (E(1/2) = -1.40 and 0.52 V vs SCE) and two irreversible one-electron oxidation processes (E(pc) = 1.54 and 1.66 V vs SCE).     

三甲硅基醚的断裂研究

Sommer等[1]首次应用（Me3SiO）2SO2向醇羟基引人三甲硅基（TMS）以保护羟基以来，已发展出很多方便有效的向醇羟基引人TMS保护基团的方法[2]．通常，立体阻碍越小的醇，其羟基越容易被硅基化，而且该TMS保护基团也就越容易在酸或碱性条件下被水解脱除[2]我们在天然产物PrehisPanolone的合成中[3]，羟基r-丁烯酸内酯2是一个关键的中间体．如何脱除前体三甲硅基醚的r-丁烯酸内酯1中的TMS保护基团是一个关键的问题．我们采用四了基氟化铵（TBAF）[4]（A）、酸性水解[5]（B）、碱性醇解[6]（C）和三氟化硼乙醚溶液（BF3-Et2O）[7]…     

Trifluoropropynylxenon(II) tetrafluoroborate [CF3C[triple bond]CXe] [BF4]--isolation of an alkynylxenon(II) compound for the first time

The salt [CF3C[triple bond]CXe] [BF4] was prepared as neat compound by the reaction of the hitherto unknown alkynyldifluoroborane CF3C[triple bond]CBF2 with XeF2 in 1,1,1,3,3-pentafluoropropane (PFP) at -45 degrees C in 59% yield. [CF3C[triple bond]CXe] [BF4] was unambiguously characterised by multinuclear NMR spectroscopy in anhydrous HF (aHF) solution.     

野黄芩素的合成与表征

本文以3,4,5-三甲氧基苯酚与对甲氧基肉桂酰氯为原料,在三氟化硼-乙醚络合物催化下,发生Friedel–Crafts反应,生成9-羟基-5,6,7,4’–四甲氧基查尔酮;然后9-羟基-5,6,7,4’–四甲氧基查尔酮在碘的二甲基亚砜溶液中发生分子内环合得到5,6,7,4’-四甲氧基黄酮;最后在酸性条件下,5,6,7,4’-四甲氧基黄酮发生去甲基化水解反应制得野黄芩素,总产率达到54%。化合物结构经IR,1H NMR和MS表征。该方法简单易行,具有广泛的应用前景。     

Evidence for the formation of terminal hydrides by protonation of an asymmetric iron hydrogenase active site mimic

Treatment of [Fe2(mu-pdt)(CO)6] [pdt=S(CH2)3S] with dppe (Ph2PCH2CH2PPh2) in refluxing toluene affords the asymmetric complex [Fe2(mu-pdt)(CO)4(dppe)] (1). Protonation of 1 with HBF4-Et2O in CH2Cl2 gives at room temperature the mu-hydrido derivative [Fe2(mu-pdt)(CO)4(dppe)(mu-H)](BF4) (2). Monitoring the reaction by 1H, 31P, and 13C NMR at low temperature reveals unambiguously that the process of the protonation of 1 implies terminal hydride intermediates.     

功能化离子液体[bmim]OTs催化乙酰化反应

以离子液体1-丁基-3-甲基咪唑四氟硼酸盐([bmim]BF4)为溶剂,对甲基苯磺酸根(OTs-)为阴离子的功能化离子液体[bmim]OTs为催化剂进行苯甲醇的乙酰化反应.结果表明,该体系循环使用10次后仍能保持良好的催化活性和稳定性,并对各种(伯、仲、叔)醇类、酚类和胺类化合物的乙酰化反应表现出良好的普适性.核磁共振波谱(13C NMR)分析结果表明,具有亲核性的[bmim]OTs和酰化试剂乙酸酐(Ac2O)形成的活性中间体AcOTs,是催化反应的活性物种.     

Synthesis of functional meso-aryl porphomonomethenes and porphodimethenes: application to the preparation of a chiral calix[4]phyrin dimer

Reaction of 5,5-dimethyldipyrromethane (1) with electron-deficient aryl aldehydes in the presence of BF(3)-Et(2)O and NH(4)Cl in propionitrile constitutes efficient, easy access to unprecedented, functional porphomonomethenes together with the expected porphodimethenes (calix[4]phyrins). Alternatively, when the reaction was carried out in CH(2)Cl(2) in the presence of an acid and Florisil, the expected bis-arylcalix[4]phyrin was isolated in 41% yield, while no scrambled macrocycle was detected. After reduction of the nitro function, porphomonomethene 9 was efficiently condensed with the binaphthyl diacyl chloride (10) leading to the first chiral calix[4]phyrin dimer (11) that exhibits a moderate enantiorecognition toward the enantiomers of malic acid.     

烯丙基缩水甘油醚的合成

烯丙醇和环氧氯丙烷在三氟化硼乙醚络合物的催化作用下进行加成和环化反应制得标题化合物。研究了催化剂用量、反应原料配比及碱用量对产物收率的影响。     

Stoichiometric and catalytic oxidations with hypervalent organo-lambda3-iodanes

Isolation, characterization, and reaction of the activated iodosylbenzene monomer, hydroxy(phenyl)iodonium ion, as a complex with 18-crown-6 (18C6) are reported. The reaction of iodosylbenzene with HBF(4) in the presence of 18C6 afforded the hydroxy-lambda(3)-iodane complex PhI(OH)BF(4).18C6 as stable yellow prisms. X-ray structure analysis indicated that the close contacts between the iodine(III) and the three adjacent oxygen atoms of 18C6 will be responsible for the increased stability of the complex compared to the uncomplexed PhI(OH)BF(4). The aqua complex of the activated iodosylbenzene, PhI(OH)OTf.18C6.H(2)O, with a water molecule coordinated to iodine(III) was also prepared. These crown ether complexes are highly reactive and serve as versatile stoichiometric oxidants, especially in water. Thus, the complexes undergo oxidative transformations of a variety of functional groups such as olefins, alkynes, enones, silyl enol ethers, sulfides, and phenols under mild conditions. The latter part reports on the iodobenzene-catalyzed alpha-oxidation of ketones, in which diacyloxy(phenyl)-lambda(3)-iodanes generated in situ act as real oxidants of ketones and m-chloroperbenzoic acid (m-CPBA) serves as a terminal oxidant. The oxidation of a ketone with m-CPBA in acetic acid in the presence of a catalytic amount of iodobenzene, BF(3)-Et(2)O, and water at room temperature affords an alpha-acetoxy ketone in good yield. It is noted that the use of water and BF(3)-Et(2)O is crucial to the success of this alpha-acetoxylation.     

BF3-mediated additions of organolithiums to ketimines: X-ray crystal structures of BF3-ketimine complexes

[reaction: see text] Additions of lithium acetylides and n-BuLi to N-alkyl ketimines mediated by BF(3)-Et(2)O in THF afford hindered tert-alkylamines in moderate to good yields. Stereochemical results and crystal structures of three BF(3)-imine complexes suggest that allylic strain strongly influences conformation and may be an important determinant of reactivity and selectivity.