2,6-二甲基-3,5-二乙氧羰基-1,4-二氢吡啶的二-π甲烷光重排反应

合成了2,6-二甲基-3,5-二乙氧羰基-1,4-二氢吡啶,并研究了它在紫外光(366nm)照射下的光化学反应。结果表明,主要的光化产物为2,6-二甲基-3,5-二乙氧羰基吡啶(占95%)其次是少量的二-π甲烷光重排产物,1,3-二甲基-2-氮杂-4,5-二乙氧羰基-双环-[3、1、0]-己烯-3(占5%)。     

N,N′-二-(3,5-二甲基苯基)-3,6-二甲基-1,4-二氢-1,2,4,5-四嗪-1,4-二甲酰胺的合成

1,2,4,5-四嗪衍生物具有抗肿瘤,杀菌,杀虫等活性,我们曾合成了具有抗肿瘤活性的N,N′-二苯基-3,6-二甲基-1,4-二氢-1,2,4,5-四嗪-1,4-二甲酰胺(3a)[1,2,3],合成路线见图1.研究它们的抗肿瘤活性时发现该化合物的苯环间位若以N,N-二甲基取代,对小鼠白血病细胞(P-388)和人肺腺癌细胞(A-549)有很强的抗肿瘤活性.     

2,2-二甲基-3,4-二溴-7,8-二乙酸基色烯的合成

本文合成了2,2-二甲基-3,4-二7,8-二乙酸基色烯,主要想通过溴的引入改变色烯3,4位双键的性质,视其对活性的影响, 也为用溴标记探讨这类激素在昆虫体内参与细胞蛋白烷基化的代谢过程提供一条途径。色满/D 5     

2,7-二甲氧基-3,6-二苯氧基萘的合成

以3,6-二溴-2,7-二羟基萘为起始原料,与硫酸二甲酯经甲醚化反应得3,6-二溴-2,7-二甲氧基萘(2);2与苯酚在碘化亚铜催化下经取代反应合成了新化合物——2,7-二甲氧基-3,6-二苯氧基萘,总收率82.5%,其结构经1H NMR,13C NMR,ESI-MS和元素分析表征。     

(4-甲基-1,3-二噻烷-2-亚甲基)-1,7-二芳基-1,6-二烯-3,5-二酮的合成

从2,4-戊二酮和1,2,3-三溴丙烷出发合成了一类新的α-羰基二硫缩烯酮类化合物,并以其为底物合成了(4-甲基-1,3-二噻烷-2-亚甲基)-1,7-二芳基-1,6-二烯-3,5-二酮类化合物,通过IR和1H NMR方法对其进行了表征.     

1,4-二硝基-2,3-二硝胺基哌嗪的合成

本文以乙二胺, 乙二醛和脲为原料, 通过Mannich反应, 合成出2,5,7,9-四氮杂双环[4.3.0]壬-8-酮盐酸盐(1); 化合物1 亚硝化给出2,5-二亚硝基-2,5,7,9-四氮杂双环[4.3.0]壬-8-酮(2); 硝化化合物2制得2,5,7,9-四硝基-2,5,7,9-四氮杂双环[4.3.0]壬-8-酮(3); 化合物3水解制得1,4-二硝基-2,3-二硝胺基哌嗪(4).     

1,8-二羟基-9,10-二氢蒽的合成

以1,8-二羟基蒽醌为原料,经甲醚化,锌粉和金属钠还原,去甲基等4步反应合成1,8-二羟基-9,10-二氢蒽,总产率为37.1,8-二甲氧基蒽醌用NaBH₄/CF₃COOH还原生成二聚产物,并测定了其单晶结构.     

1,1-二氨基-2,2-二硝基乙烯的合成研究进展

1,1-二氨基-2,2-二硝基乙烯（FOX-7）是一种低感度高能量的新型含能材料.现有的1,1-二氨基-2,2-二硝基乙烯的合成包括以2-甲基咪唑、盐酸乙脒与乙二酸二乙酯、2-甲基-4,6-二羟基嘧啶为前体的三条合成路线.使用硫酸/硝酸体系硝化2-甲基-4,6-二羟基嘧啶可得到2-二硝基亚甲基-5,5-二硝基嘧啶-4,6-二酮,然后水解可得到FOX-7,正相硅胶薄层色谱可对该反应进行监测.使用曲拉通X-100/正己烷体系的反相微乳法可制备FOX-7球形纳米晶;FOX-7球形纳米晶具有良好的应用前景,对其合成工艺与路线进行探索和研究具有一定的意义.     

5,5-二甲基-2-氧代-2-(N,N-对苯二胺基-二苄基)-二-1,3,2-氧磷杂环己烷的合成及表征

以新戊二醇、三氯化磷和乙醇为原料制得中间体 5 ,5 -二甲基 -1 ,3,2 -二氧磷杂环己烷 -2 -氧 ( DPDO) ,用DPDO与由芳醛和对苯二胺缩合制得的席夫碱 SB ～ SB 加成 ,合成了膨胀型阻燃剂 5 ,5 -二甲基 -2 -氧代 -2 -( N,N -对苯二胺基 -二苄基 ) -二 -1 ,3,2 -氧磷杂环己烷 ( DPPO ～ DPPO ) ,通过元素分析 ,IR,NMR和 MS对其结构进行表征 ,并对其在醇酸清漆中的应用进行了讨论     

2,6-二氨基-3,5-二硝基吡嗪-1-氧化物的合成

研究了2,6-二氨基-3,5-二硝基吡嗪-1-氧化物(LLM-105)的合成新方法. 该方法是以2,6-二氯吡嗪和甲醇钠作为起始原料, 经烷氧基化、硝化、胺化、N-氧化四步反应得到LLM-105, 总收率为50%. 用¹H NMR, ¹³C NMR, IR, MS和元素分析对LLM-105及其中间体结构进行了表征.     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

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.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

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.     

Selective synthesis of 4,5-dihydroimidazo- and imidazo[1,5-a]quinoxalines via modified Pictet–Spengler reaction

An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

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%).     

Understanding the Diels-Alder reactivity of 1,2-azaborine analogues

The Diels-Alder reactivity of 1,2-heteroborines (H₄C₄B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.     

Synthesis of N-substituted carbazolones from α-iodo enaminones via Pd(0)-catalyzed intramolecular coupling under microwave irradiation

A variety of N-aryl and N-alkyl carbazolones were conveniently achieved in good to high yields via Pd₂(dba)₃-mediated intramolecular coupling of N-substituted α-iodo enaminones under microwave irradiation. The Pd(0)-catalyzed cyclization was found to proceed favorably with the more electron-deficient phenyl ring during the reactions involving unsymmetrical N,N-diaryl α-iodo enaminones. This unique property enables the construction of carbazolone skeleton containing nitro substituted benzenoid ring.     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

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.     

Synthesis of substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles by intramolecular nitrilimine cycloaddition

Both substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles have been synthesized by the 3+2 intramolecular dipolar cycloaddition of nitrilimines to alkynes. This cyclization has been extended to more versatile 3-bromo derivatives by the use of alkynylbromides as dipolarophiles.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

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.