对羟基苯甲醛的异戊烯烷基化反应

研究了在不同碱性条件下,对羟基苯甲醛与4-溴异戊烯的烷基化反应。通过调节反应条件可选择性地合成C-烷基化产物、O-烷基化产物或C-烷基化-O-烷基化产物。产物的结构经1H NMR,IR和MS表征。     

丙醛间苯二酚杯[4]芳烃烷基化衍生物的合成

以间苯二酚和丙醛为原料合成了丙醛杯[4]芳烃(1),1经不同的烷基化反应合成了新的丙醛杯[4]芳烃烷基化衍生物,其结构经1H NMR和IR表征。     

用KOH／Al2O3合成N—烷基咪唑

N-烷基化咪唑类化合物的合成常以咪唑为原料,在强碱的作用下,经烷基化反应而获得。方法有醇钠或氨基钠与咪唑反应,生成咪唑负氮离子,然后再与烷基化试剂反应以及在相转移催化下咪唑与烷基化试剂的反应。近年来,应用无机载体试剂进行各种有机合成反应已引起人们的广泛兴趣。我们以KOH/Al_2O_3为载体试剂合成了10种N-烷基咪唑衍生物,收率一般在80%以上。其中某些反应室温下即可完成,操作十分简便。且载体经再生后使用活性不变。     

金催化的吲哚与末端炔烃的分子间烷基化反应

尝试了用金(Au)催化吲哚和炔烃的Friedel-Crafts烷基化反应, 具体探讨了金(I)配合物催化吲哚与末端炔烃的烷基化反应的条件, 并制备了一系列尚未见文献报道的双取代β-吲哚烷基化衍生物. 产物的结构经1H NMR, 13C NMR, MS和元素分析确证. 并对其反应机理可能性进行了推测.     

西部松小蠹集合信息素(±)-exo-Brevicomins的合成

以丙炔醇为起始原料,经烷基化、炔键移位、氧化、环化等反应合成了西部松小蠢集合信息素。     

乙拉西坦的合成

2-吡咯烷酮经N-烷基化、氨解反应合成了乙拉西坦,总收率42．6％。其结构经^1H NMR,^13C NMR和IR表征。     

合成盐酸芬戈莫德的工艺改进

以溴苯为原料,经Wurtz偶联反应、Friedel-Crafts反应、烷基化反应等合成了免疫抑制剂盐酸芬戈莫德,总收率23.6%,其结构经1H NMR,IR和ESI-MS确证。     

偶联剂2-(4-异硫氰基苄基)-1,4,7,10-四氮杂环十二烷四乙酸的合成工艺改进

以对硝基苯丙氨酸和乙二胺为原料,经酯化、胺解、成环、烷基化、还原、取代等反应合成了目标产物2-(4-异硫氰基苄基)-1,4,7,10-四氮杂环十二烷四乙酸(p-SCN-Bz-DOTA),总产率为10.4%。反应中使用NaBH4/BF3体系代替甲硼烷作为还原剂,提高了操作过程的安全性;使用溴乙酸叔丁酯代替溴乙酸作为烷基化试剂,提高了烷基化的反应产率,而且避免了使用制备型高效液相色谱,降低了合成成本。     

Beta沸石上合成对叔丁基苯酚和2,4—二叔丁基苯酚

首次在三相条件下,在Ｂｅｔａ沸石催化剂上研究了苯酚与异丁烯烷基化合成对叔丁基苯酚和２,４－二叔丁基苯酚。通过对Ｈｂｅｔａ沸石高温焙烧和吡啶中毒试验研究了烷基化反应活性和选择性的变化规律;用ＮＨ３－ＴＰＤ和Ｐｙ－ＩＲ测定了试样的酸量和酸种类,结果表明Ｈｂｅｔａ沸石具有很好的烷基化活性,苯酚的转化率可达９２％,经１１２３Ｋ焙烧后苯酚转化率为８８％,对叔丁基苯酚和２,４－二叔丁基苯酚的选择性分别为７０～７５％和１４～２０％,中等强度的Ｂｒｎｓｔｅｄ酸是苯酚与异丁烯烷基化反应的活性中心。粘合剂含量低于３０％对烷基化活性基本无影响     

新型甲磺酰基喹啉衍生物的合成

以7-羧基喹啉为原料,经硝化、酯化、喹啉环和硝基的还原、磺酰化和烷基化反应合成了7个新型的甲磺酰基喹啉衍生物,其结构经1H NMR和LC-MS表征。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.