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1.
焦纶基  王琳 《合成化学》1997,5(1):83-86
由6,6-二烷基富烯与烯丙基格氏试剂加成所得到的取代环戊二烯基负离子与芳酰氯反应,合成了5个未见文献报道的6-羟基富烯化合物(1 ̄5)。用此类化合物与羟胺反应,合成了5个新的环戊二烯并[d]恶嗪化合物(6 ̄10),其结构经IR,^1H NMR和元素分析证实。  相似文献   

2.
Grignard试剂同6,6-二烷基富烯反应的研究   总被引:2,自引:0,他引:2  
烯丙基卤化镁和环戊二烯基溴化镁同6,6-二烷基富烯分别进行富烯环外双键的加成和还原反应,生成的取代环戊二烯基负离子用(CpTiCl_2)_2O(Cp=环戊二烯基)或TiCl4配合,合成通式为Cp(C_5H_1-CRR ̄1-CH_2CH=CH_2)TiCl_2和(C_5H_4CHRR ̄1)_2TiCl_2的化合物。对烯丙基卤化镁、环戊二烯基溴化镁同富烯的反应机理进行了探讨。  相似文献   

3.
苄基钠与6,6-二烷基富烯及6,6-n亚甲基富烯(n=4,5,6)皆发生富烯环外双键的加成反应。产生的取代环戊二烯基负离子与TiCl4、ZrClr及(CpTiCl2)2O络合,合成出22种新的含或不含手性碳取代茂铁、锆化合物。讨论了反应机理及^1H NMR谱。  相似文献   

4.
苄基钠与6,6-二烷基富烯及6,6-n亚甲基富烯(n=4,5,6)皆发生富烯环外双键的加成反应。产生的取代环戊二烯基负离子与TiCl_4、ZrCl_4及(CpTiCl_2)_2O络合,合成出22种新的含或不含手性碳取代茂钛、锆化合物。讨论了反应机理及~1HNMR谱。  相似文献   

5.
Grignard试剂同6,6—二烷基富烯反应的研究   总被引:2,自引:0,他引:2  
烯丙基卤化镁和环戊二烯基溴化镁同6,6-二烷基富烯分别进行富烯环外双键的加成和还原反庆,生成的取代环戊二烯基负离子用(CpTiCl2)2O(Cp=环戊二烯基)或TiCl4配合,合成式为Cp(C6H4-CRR^1-CH2Ch-CH2)TiCl2和(C6H4CHRR^1)2TiCl2的化合物,对烯丙基卤化镁、环戊二烯基溴化镁同富烯的反应机理进行了探讨。  相似文献   

6.
1-芳酰基-3-烷基-6-羟基-6-芳基富烯的合成焦纶基,董育斌,马玉道(山东大学应用化学研究所,济南,250100)关键词富烯,二茂铁,芳酰化,合成前文[1]曾报道过甲基锂、苯基锂与6,6-二烷基富烯加成物的芳酰化。为进一步探讨取代环戊二烯负离子的...  相似文献   

7.
以6,6-二烷基富烯与甲基锂、苯基锂或对甲苯基锂所犁 取代环戊二烯基锂与三甲基氯硅烷反应,合成了11个新的三甲基硅基环戊二烯化合物,其结构经元素分析、IR和^1HNMR确证。  相似文献   

8.
二苯膦基锂与6,6-二甲基富烯发生环外双键的加成反应,生成含膦取代环戊二烯基负离子(Ⅰ),它与FeCl2络合,生成1,1',二(1-二苯膦基-异丙基)茂铁(Ⅱ)。(Ⅱ)与PdCl2(PhCN)2反应,生成杂双核络合物(Ⅲ)。茂铁(Ⅱ)为单斜晶系,空间群P21/c,晶胞参数a=1.3382(5)nb,b=0.8550(1)nm,c=1.7309(4)nm,β=109.16(2)°,V=1.87082  相似文献   

9.
以香叶醇(3)和高香叶基碘(6)为起始原料合成了(±)-MalabaricAcid(1)和Anisomelol(2)前体化合物9和11,合成中的关键步骤是化合物5和7的Wadsworth-Emmons反应以及化合物8和10的烯丙型区域选择性氯化重排。  相似文献   

10.
焦纶基  王琳  马玉道  宋淳 《有机化学》1996,16(4):372-375
本文以6, 6-二烷基富烯与烯丙基格氏试剂反应所得的取代环戊二烯基负离子与芳酰氯反应, 合成了5个新的6-羟基富烯化合物(1-5)。用此化合物与肼反应, 合成了5个新的环戊二烯并[d]哒嗪化合物(6-10)。通过^1H NMR、IR及元素分析确定了它们的结构。  相似文献   

11.
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%.  相似文献   

12.
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.  相似文献   

13.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

14.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

19.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

20.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

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