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1.
Mingjian Yuan Xiaodong Yin Haiyan Zheng Canbin Ouyang Zicheng Zuo Huibiao Liu Yuliang Li 《化学:亚洲杂志》2009,4(5):707-713
Bright funnels : A series of dendritic systems, which are capable of funneling energy from the periphery to the core, have been synthesized. The photophysical properties of dendrimers have been determined. Selective excitation of the donor leads to an efficient energy transfer (>90 %) to the acceptor. The approach provides a facile synthesis for the modification of near‐infrared BF2‐Azadipyrromethenes.
2.
Alois Fürstner Prof. 《Angewandte Chemie (International ed. in English)》2009,48(8):1364-1367
Sleeping beauty? Is the scientific community about to kiss awake iron catalysis, a topic that has been dormant for decades? A recent study on a user‐friendly direct cross‐coupling reaction of alkyl and aryl halides constitutes an important step toward this end through the integration of two different iron‐catalyzed elementary steps into a practical one‐pot procedure.
3.
Anthony S. R. Chesman David R. Turner Dr. Glen B. Deacon Prof. Stuart R. Batten Assoc. Prof. 《化学:亚洲杂志》2009,4(5):761-769
Additional cyclization : Dicyanonitrosomethanide, [C(CN)2(NO)]? undergoes nucleophilic addition and cyclization of 1,2‐diaminoethane and 1,3‐diaminopropane on the nitrile groups to form imidazolinyl and 1,4,5,6‐tetrahydropyrimidinyl groups, respectively. Ethanolamine has lower reactivity and fails to cyclize.
4.
A stereocontrolled total synthesis of the cytotoxic spiroacetal‐containing polyketide (?)‐spirangien A is described. This utilizes an aldol‐based strategy to construct a common stereotetrad intermediate that was elaborated into the spiroacetal core, followed by the introduction of the unstable pentaene‐containing side chain, performed with exclusion of light, using sequential Stille cross‐coupling reactions.
5.
Jasmin Mecinović Refaat B. Hamed Christopher J. Schofield Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(15):2796-2800
Three of a kind : Vicinal tricarbonyl compounds undergo C? C cleavage mediated by ferric ions (see scheme). The observed cleavage of ninhydrin and dehydroascorbic acid has relevance for amino acid detection and the metabolism of vitamin C.
6.
StephenP. Thomas VarinderK. Aggarwal 《Angewandte Chemie (International ed. in English)》2009,48(11):1896-1898
A breakthrough in the asymmetric hydroboration of notoriously difficult 1,1‐disubstituted alkenes using a new family of highly effective hydroboration reagents is described (see scheme). The intermediate boranes can be oxidized to alcohols or used in Suzuki–Miyaura cross‐coupling reactions.
7.
Eric J. Klinker Dr. Sason Shaik Prof. Dr. Hajime Hirao Dr. Lawrence Que Jr. Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(7):1291-1295
It's in the bond : The cleavage of C? H bonds by two related oxoiron(IV) complexes shows a range of kinetic isotope effect (KIE) values that exhibit an unusual dependence on the C? H bond strength. Large nonclassical KIEs are observed for bond strengths below 93 kcal mol?1, while semiclassical values are found above this value (see graph, DHA=9,10‐dihydroanthracene). This nonintuitive behavior can be rationalized by invoking a two‐state reactivity model.
8.
Akinari Hamajima Minoru Isobe 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2009,121(16):2985-2989
Eines der Haupttoxine bei Fischvergiftungen, das Ciguatoxin (siehe Struktur), war Ziel einer Totalsynthese. Der Syntheseweg beruht auf der Kupplung dreier Segmente, und die Schlüsselumwandlungen umfassen eine Komplexbildung zwischen Acetylen und Dicobalthexacarbonyl.
9.
Mikio Nakamura Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(15):2638-2640
Iron man or weakling? Ligand‐field strengths are conveniently expressed by the empirical spectrochemical series. Although cyanide has been deeply entrenched as a strong‐field ligand, a couple of recent examples cast doubt toward the position of this ligand, namely the high‐spin (S=2) states of [CrII(CN)5]3? and [FeII(tpp)(CN)]?. tpp=meso‐tetraphenylporphinate.
10.
StephenL. Craig 《Angewandte Chemie (International ed. in English)》2009,48(15):2645-2647
Charging forward : Ionic interactions presented in a multivalent fashion in small‐molecule ionic liquids lead to functional polymer‐like materials (see picture) that are consistent with the formation of a supramolecular ionic network. For example, the ionic material formed from a dication consisting of two covalently linked tetraalkyl phosphonium moieties and a porphyrin tetracarboxylate has a viscosity of 106 Pa s at 25 °C.
11.
Natsumi Tanaka Takahiro Suzuki Dr. Takehiko Matsumura Yosuke Hosoya Masahisa Nakada Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(14):2580-2583
Intelligent design : The total synthesis of the cytotoxic (?)‐FR182877 relies on 1) tandem Diels–Alder reactions to close rings A–D (see scheme), 2) a palladium‐mediated 7‐exo‐trig reaction, and 3) an iridium‐mediated isomerization followed by epimerization and stereoselective reduction.
12.
Tsang‐Chi Lee Chiung‐Fang Chang Yuan‐Chieh Chiu Yun Chi Tzu‐Ying Chan Yi‐Ming Cheng Chin‐Hung Lai Pi‐Tai Chou Gene‐Hsiang Lee Chen‐Han Chien Ching‐Fong Shu Jens Leonhardt 《化学:亚洲杂志》2009,4(5):742-753
Long live the OLED! Rational design and synthesis of IrIII complexes bearing two cyclometalated ligands (C N) and one 2‐(diphenylphosphino)phenolate chelate (P O) as well as the corresponding IrIII derivatives with only one (C N) ligand and two P O chelates are reported. According to the observed photophysical data, a P O ligand is found to be able to fine‐tune the light‐emitting electronic transition of these complexes.
13.
14.
Ken‐ichi Shimizu Dr. Ryosuke Sato Atsushi Satsuma Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(22):3982-3986
Let's drink to that! Two alcohols (one primary and one secondary) can be coupled in an atom‐efficient process by a hydrogen‐autotransfer catalytic system in the form of silver subnanoclusters supported on γ‐Al2O3. The recyclable heterogeneous catalyst promoted the one‐pot C? C cross‐coupling in the presence of a catalytic amount of the weak base Cs2CO3 (see reaction mechanism).
15.
Jian Zhang Dr. Tao Wu Cong Zhou Shumei Chen Dr. Pingyun Feng Prof. Dr. Xianhui Bu Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(14):2542-2545
B‐hive? A family of crystalline materials analogous to porous AlPO4 but based on boron imidazolate frameworks (BIFs) can be formed by the crosslinking of various presynthesized boron imidazolates with monovalent cations (Li+ and Cu+, see picture). This synthetic method is capable of generating a large variety of open frameworks, ranging from the four‐connected zeolitic sodalite type to the three‐connected chiral (10,3)‐a type.
16.
Lin Li Yu‐Peng Tian Jia‐Xiang Yang Ping‐Ping Sun Jie‐Ying Wu Hong‐Ping Zhou Sheng‐Yi Zhang Bao‐Kang Jin Xiao‐Juan Xing Chuan‐Kui Wang Ming Li Guang‐Hua Cheng Huo‐Hong Tang Wen‐Hao Huang Xu‐Tang Tao Min‐Hua Jiang 《化学:亚洲杂志》2009,4(5):668-680
Mark us bent! The synthesis, structure, and single‐ and two‐photon spectroscopic properties of a series of pyrimidine‐based (bent‐shaped) molecules are reported. These allow structure‐property relationships and guidelines for both the development and application of TPA compounds to be derived.
17.
Shin Aoki Prof. Yumiko Tomiyama Yoshiyuki Kageyama Dr. Yasuyuki Yamada Dr. Motoo Shiro Dr. Eiichi Kimura Prof. 《化学:亚洲杂志》2009,4(4):561-573
Conditional cleavage : Photochemical S? N bond cleavage of the Zn2+ complex of N‐dansylcyclen (ZnL2) in aqueous solution was investigated. Moreover, photolysis of ZnL2 (see scheme) facilitated photoreversion of cis,syn‐thymine photodimer (T[c,s]T).
18.
Hana Prokopcov C.Oliver Kappe 《Angewandte Chemie (International ed. in English)》2009,48(13):2276-2286
New kid on the block : The cross‐coupling of thioorganic compounds with boronic acids under neutral conditions in the presence of catalytic palladium(0) and a stoichiometric amount of a copper(I) oxygenate has emerged as a very useful method for the construction of C C bonds (see scheme). This intriguing and mechanistically unprecedented base‐free coupling has distinct advantages, in particular when traditional Pd0‐catalyzed cross‐coupling is not possible.
19.
Yann Gloaguen Gilles Alcaraz Dr. Anne‐Frédérique Pécharman Eric Clot Dr. Laure Vendier Dr. Sylviane Sabo‐Etienne Dr. 《Angewandte Chemie (International ed. in English)》2009,48(16):2964-2968
A question of coordination mode : Two new borane compounds are prepared. They act as bifunctional ligands as illustrated by their reaction with ruthenium polyhydrides which leads to the formation of two complexes (see scheme) displaying either a δ‐agostic interaction of a η2‐B? H bond involving a trivalent boron atom or a dihydroborate ligation.
20.
Playing the sax : The enantioselective total syntheses of (?)‐ and (+)‐decarbamoyloxysaxitoxin (doSTX) and (+)‐saxitoxin (STX) are reported. A new methodology was developed for the synthesis of STXs, featuring discriminative reduction of the nitro group and N? O bond in nitroisoxazolidine.