Abnormal Reaction of 1-(2′-Methoxybenzoyl)-1-(2′-hydroxy-5′-methoxycarbonylbenzoyl)methane Treated with Etyyl Orthoformate and Acetic Anhydride

邻羟基二苯甲酰基甲烷与Ａｃ２Ｏ和ＨＣ（ＯＥｔ）３反应通常是ＨＣ（ＯＥｔ）３作为酰化剂，得到３－苯甲酰基色酮。本文报道５－甲氧羰基－２－羟基苯甲酰基－（２′－甲氧苯甲酰基）甲烷与Ａｃ２Ｏ和ＨＣ（ＯＥｔ）３反应时，是Ａｃ２Ｏ而不是ＨＣ（ＯＥｔ）３作为酰化剂，生成３－苯甲酰基－２－甲基色酮。其结构经ＮＭＲ、ＭＳ、ＩＲ和ＥＡ证实。并对其反应机理作了讨论。     

1—（5‘—甲氧羰基—2’—羟基苯甲酰基（—1—（2‘—甲氧苯甲酰基）甲烷与Ac2O和HC...

邻羟基二苯甲酰基甲烷与Ａｃ２Ｏ和ＨＣ（ＯＥｔ）３反应通常是ＨＣ（ＯＥｔ）３作为酰化剂，得到３－苯甲酰基色酮。本文报道５－甲氧羰基－２－羟基苯甲酰基－（２＇－甲氧苯甲酰基）甲烷与Ａｃ２Ｏ和ＨＣ（ＯＥｔ）ｓ反应时，是Ａｃ２Ｏ而不是ＨＣ（ＯＥｔ）作为酰化剂，生成３－苯甲酰基－２－甲基色酮。其结构经ＮＭＲ、ＭＳ、ＩＲ和ＥＡ证实。并对其反应机理作了讨论。     

氨基硫脲纤维素分离富集FAAS法测定金

氨基硫脲纤维素分离富集ＦＡＡＳ法测定金候贤灯，李从容，张汉萍，苏庆平（成都理工学院应用化学系，６１００５９）纤维素是一种重要的工业和化学原料，它是由六碳链节——Ｏ－（ＣＨ－（ＣＨＯＨ）＿２－ＣＨ——ＨＯＣＨ＿２ＣＨ───—Ｏ构成的。如果在纤维素的羟基...     

磷酸钙骨水泥水化过程的XRD实时分析

采用ＸＲＤ实时分析方法,研究了磷酸钼骨水泥水化过程中反应物磷酸四钙（ＴｅｔｃＰ）和二水磷权氢钙（ＤＣＰＤ）的消失过程,以及生成物羟基磷灰石（ＯＨＡｐ）的形成过程。结果表明,ＤＣＰＤ比ＴｅｔＣＰ溶解速度快而先耗尽,水化反应的速度受ＴｅｔＣＰ控制,水化产物的主晶相为结晶ＯＨＡＰ。方法简单易行,合理可靠,能够准确实时体现水化反应的动态过程。     

水热法合成羟基磷灰石的结构和形貌

羟基磷灰石是一种微溶于水的弱碱性磷酸钙盐 (Ｃａ10 (ＰＯ4 ) 6 (ＯＨ) 2 ,ＨＡ) [1] ,多用于人体硬组织(骨、牙 )的修复替换[2 ] 。与人类骨骼相比 ,致密羟基磷灰石仍然表现出较低的力学性能[3] 。由于针棒状的晶体具有较低的位错密度 ,较高的抗拉性能[4 ] 。近年来 ,针状或棒状羟基磷灰石的合成已引起广泛关注。合成ＨＡ的方法有固态反应法[5] 、液相沉淀法[6 ] 、溶胶 凝胶法[7,8] 及溅射法[9] 等 ,但只有少数几种方法能够对产物的形貌进行控制。虽然采用水热法在 2 0 0℃和 2ＭＰａ下合成了羟基磷灰石晶须[10 ] ,但实验步骤较为复杂 ,…     

蜜蜂外激素9—ODA和9—HDA的合成

６－溴－２－己酮在Ｌｉ２ＣｕＣｌ４催化下与γ－溴代巴豆酸甲酯进行格氏偶联，合成王物质９－羰基－（Ｅ）－２癸烯酸（９－ＯＤＡ），将其还原得到了另一蜂王物质９－羟基－（Ｅ）－２－癸烯酸（９－ＨＤＡ）。该法是合成９－ＯＤＡ和９－ＨＤＡ的新路线。     

不同异氰酸酯固化的蓖麻油／酚氧树脂聚氨酯的力学性能

以ＢＦ３·ＯＥｔ２为催化剂，４，４－二羟基二苯基丙烷与环氧氯丙烷反应，生成端羟基的酚氧树脂（Ａ），Ａ与蓖麻油（Ｂ）混合，用３种异氰酸酯（ＴＤＩ、ＩＰＤＩ和ＨＤＩ）作为固化剂，制得交联聚氨酯。研究了这３种聚氨酯的力学性能及形态与组成和二异氰酸酯结构的关系；改变ＮＣＯ／ＯＨ摩尔比及Ｂ与Ａ的质量比，可以制得具有较好力学性能的聚氨酯材料。蓖麻油，酚氧树脂，聚氨酯，力学性能     

新型钙离子选择电极的研制

以羟基磷灰石［Ｃａ１０（ＰＯ４）６（ＯＨ）２］为活性材料的钙离子选择电极，容易制作，重现性和稳定性好，适宜较宽ｐＨ范围，具有较好选择性，线性范围为１．１×１０－１～１×１０－５ｍｏｌ／Ｌ，用于钙离子测定结果令人满意     

蜜蜂外激素9－ODA和9－HDA的合成

６－溴－２－己酮在Ｌｉ２ｃｕＣｌ４催化下与γ－溴代巴豆酸甲酯进行格氏偶联，合成了蜂王物质９－羰基－（Ｅ）－２－癸烯酸（９－ＯＤＡ），将其还原得到另一蜂王物质９－羟基－（Ｅ）－２－癸烯酸（９－ＨＤＡ）。该法是合成９－ＯＤＡ和９－ＨＤＡ的新路线。     

甲烷单加氧酶的催化机理

研究了来源于Ｍｅｔｈｙｌｏｍｏｎａｓｓｐ．ＧＹＪ３菌的甲烷单加氧酶（ＭＭＯ）催化机理，结果表明，用还原剂处理基于酶可得么不同还原态的羟基化酶，其中全还原态的羟基化酶具有ＭＭＯ催化活性，还原酶和调节蛋白单独存在的均没有ＭＭＯ活性，确定了羟基化酶组分是ＭＭＯ的催化活性中心，用紫外光谱法证实了ＮＡＤＨ和还原酶之间的相互作用，即还原酶接受ＮＡＤＨ的电子，使氧化态的ＦＡＤ转化为还原态的ＦＡＤ，ＭＭＯ的电子传     

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%.     

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.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

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.