相转移催化合成对甲氧基肉桂酸-2-乙基己酯的研究

对甲氧基肉桂酸 2 乙基己酯是一种有效的ＵＶＢ防晒剂[1 ,2 ] ,一般采用Ｃｌａｉｓｅｎ Ｓｃｈｍｉｄｔ缩合反应制得[3] ,但由于催化剂ＫＯＨ处于水相 ,对反应物不能充分起到催化作用导致产率较低[4] 。我们利用乙二醇 (ＰＥＧ)为相转移催化剂合成立体专一的反式对甲氧基肉桂酸 2 乙基己酯 ,产率提高到 72 .5 %。合成路线如下 :1　实验部分1 .1　仪器与试剂ＢＩＯ ＲＡＰＦＴ45 0红外光谱仪 ,用液膜法测试 ;Ｂｒｕｒｅｒ ＡＭ 30 0超导核磁共振仪 (溶剂ＤＣ Ｃｌ3) ;ＭＡＴ/44Ｓ ,ＧＣ ＭＳ型色质联用谱仪 ;试剂均为分析纯 ,上海化学试剂…     

以混合模板剂合成TS-1分子筛及其性能研究

以四丁基溴化铵（ＴＢＡＢｒ）＋四乙基氢氧化铵（ＴＥＡＯＨ，ｎ（ＴＢＡ＋）／ｎ（ＴＥＡ＋）＝１）或以四丙基溴化铵（ＴＰＡＢｒ）＋ＴＥＡＯＨ为模板剂，钛酸四丁酯和正硅酸乙酯为原料，于１７０℃水热合成出ＴＳ１分子筛．对合成的ＴＳ１样品进行了ＸＲＤ，ＦＴＩＲ，ＳＥＭ和ＢＥＴ比表面积分析，证实了样品中钛已进入Ｓｉｌｉｃａｌｉｔｅ１骨架．选择戊烷氧化为探针反应，考察了ＴＳ１的催化活性．结果表明以ＴＥＡＯＨ为碱，合成的样品晶粒较大，达到４～１０μｍ，用氨水和ＴＥＡＯＨ调节反应液的碱度，对晶体的生长和形貌的影响各不相同．文中还就ＴＥＡＯＨ引入的作用进行了讨论．     

以混合模板剂合成TS—1分子筛及其性能研究

以四丁基溴化铵（ＴＢＡＢｒ）＋四乙基氢氧化铵（ＴＥＡＯＨ，ｎ（ＴＢＡ＾＋）／ｎ（ＴＥＡ＾＋）＝１）或以四丙基溴化铵（ＴＰＡＢｒ）＋ＴＥＡＯＨ为模板剂，钛酸四丁酯和正硅酸乙酯为原料，于１７０℃水热合成出ＴＳ－１分子筛。对合成的ＴＳ－１样品进行了ＸＲＤ，ＦＴ－ＩＲ，ＳＥＭ和ＢＥＴ比表面积分析，证实了样品中钛已进入Ｓｉｌｉｃａｌｉｔｅ－１骨架。选择戊烷氧化为探针反应，考察了ＴＳ－１的催化活性。结果表明以     

DOUBLE SUBSTITUTE CALIBRATION FOR THE ISOTOPIC RATIO MEASUREMENT AMONG RARE EARTH ELEMENTS

ＤＯＵＢＬＥＳＵＢＳＴＩＴＵＴＥＣＡＬＩＢＲＡＴＩＯＮＦＯＲＴＨＥＩＳＯＴＯＰＩＣＲＡＴＩＯＭＥＡＳＵＲＥＭＥＮＴＡＭＯＮＧＲＡＲＥＥＡＲＴＨＥＬＥＭＥＮＴＳ￥ＴｅｉｎｇＬｉｅｎＣＨＡＮＧ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，ＰｅｋｉｎｇＵｎ...     

BETA－CORRECTION SPECTROPHOTOMETR DETERMINATION OF COPPER ITS CHELATE＇S CHARACTERISTIC PAPAMETERS WITH o－IODOBENZENEDIAZOAMINOBENZENE－p－AZOBENZENE

ＢＥＴＡ－ＣＯＲＲＥＣＴＩＯＮ　ＳＰＥＣＴＲＯＰＨＯＴＯＭＥＴＲ　ＤＥＴＥＲＭＩＮＡＴＩＯＮ　ＯＦ　ＣＯＰＰＥＲ　ＩＴＳ　ＣＨＥＬＡＴＥ＇Ｓ　ＣＨＡＲＡＣＴＥＲＩＳＴＩＣ　ＰＡＰＡＭＥＴＥＲＳ　ＷＩＴＨ　ｏ－ＩＯＤＯＢＥＮＺＥＮＥＤＩＡＺＯＡＭＩＮＯ...     

COMPUTERIZED PREDICTION AND SYNTHESIS OF TERNARY COMPOUND ZKBr 3MnSO_4

ＣＯＭＰＵＴＥＲＩＺＥＤ　ＰＲＥＤＩＣＴＩＯＮ　ＡＮＤ　ＳＹＮＴＨＥＳＩＳ　ＯＦ　ＴＥＲＮＡＲＹ　ＣＯＭＰＯＵＮＤ　２ＫＢｒ　３ＭｎＳＯ_４ＣＯＭＰＵＴＥＲＩＺＥＤＰＲＥＤＩＣＴＩＯＮＡＮＤＳＹＮＴＨＥＳＩＳＯＦＴＥＲＮＡＲＹＣＯＭＰＯＵＮＤＺＫＢｒ?..     

含膦,氮配体的混合膦酸锆—钯催化剂的研制

用氯化二苯基膦为膦化试剂,首次对多乙烯多胺乙基膦酸－磷酸氢锆Ｚｒ（ＨＰＯ４）１．３５（Ｏ２ＰＣＨ２ＣＨ２（ＮＨＣＨ２ＣＨ２）ｍＮＨ２）０．６５·Ｈ２Ｏ（ＺＰ－ＰＥＰＡＥＰＡ,ｎ＝０,１,２,３,４）载体表面进行二苯基膦化,合成了一类含膦氮配体的新型混合膦酸锆载体及负载钯催化剂。研究了有机膦酸侧链不同链长和Ｐｈ２ＰＣｌ用量对配体载体制备的影响,并用ＩＲ,ＴＧ,ＤＴＧ,ＤＴＡ对这类载体及催化剂进行表征     

SYNTHESIS OF POLYSUBSTITUTED AROMATIC COMPOUNDS：2．THE DIELS－ALDER REACTION OF 1－CHLORO SUBSTITUTED DIENES WITH DIMETHYL ACETYLENEDICARBOXYLATE

ＳＹＮＴＨＥＳＩＳＯＦＰＯＬＹＳＵＢＳＴＩＴＵＴＥＤＡＲＯＭＡＴＩＣＣＯＭＰＯＵＮＤＳ：２ＴＨＥＤＩＥＬＳ－ＡＬＤＥＲＲＥＡＣＴＩＯＮＯＦ１－ＣＨＬＯＲＯＳＵＢＳＴＩＴＵＴＥＤＤＩＥＮＥＳＷＩＴＨＤＩＭＥＴＨＹＬＡＣＥＴＹＬＥＮＥＤＩＣＡＲＢＯＸＹＬ...     

STUDY ON THE RELATIONSHIP BETWEEN MELTING POINT AND ACID DENATURING ACIDITY OF DNA BY ULTRAVIOLET SPECTROMETER

ＳＴＵＤＹ　ＯＮ　ＴＨＥ　ＲＥＬＡＴＩＯＮＳＨＩＰ　ＢＥＴＷＥＥＮ　ＭＥＬＴＩＮＧ　ＰＯＩＮＴ　ＡＮＤ　ＡＣＩＤ　ＤＥＮＡＴＵＲＩＮＧ　ＡＣＩＤＩＴＹ　ＯＦ　ＤＮＡ　ＢＹ　ＵＬＴＲＡＶＩＯＬＥＴ　ＳＰＥＣＴＲＯＭＥＴＥＲＳＴＵＤＹＯＮＴＨＥＲＥＬＡＴ...     

SYNTHESIS OF POLYSUBSTITUTED AROMATIC COMPOUNDS 3.THE DIELS-ALDER REACTION OF PHENYLSELENO SUBSTITUTED DIENES WITH DIMETHYL ACETYLENEDICARBOXYLATE

ＳＹＮＴＨＥＳＩＳ　ＯＦ　ＰＯＬＹＳＵＢＳＴＩＴＵＴＥＤ　ＡＲＯＭＡＴＩＣ　ＣＯＭＰＯＵＮＤＳ　３．ＴＨＥ　ＤＩＥＬＳ－ＡＬＤＥＲ　ＲＥＡＣＴＩＯＮ　ＯＦ　ＰＨＥＮＹＬＳＥＬＥＮＯ　ＳＵＢＳＴＩＴＵＴＥＤ　ＤＩＥＮＥＳ　ＷＩＴＨ　ＤＩＭＥＴＨＹＬ　Ａ...     

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%.     

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.     

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.     

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%).     

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.     

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.     

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.     

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.     

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.