- Halogen Exchange Reaction of Aliphatic Fluorine Compounds with Organic Halides as Halogen Source
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The halogen exchange reaction of aliphatic fluorine compounds with organic halides as the halogen source was achieved. Treatment of alkyl fluorides (primary, secondary, or tertiary fluorides) with a catalytic amount of titanocene dihalides, trialkyl aluminum, and polyhalomethanes (chloro or bromo methanes) as the halogen source gave the corresponding alkyl halides in excellent yields under mild conditions. In the case of a fluorine/iodine exchange, no titanocene catalyst is needed. Only C-F bonds are selectively activated under these conditions, whereas alkyl chlorides, bromides, and iodides are tolerant to these reactions.
- Mizukami, Yuki,Song, Zhiyi,Takahashi, Tamotsu
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p. 5942 - 5945
(2016/01/09)
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- Solid polymer films exhibiting handedness-switchable, full-color-tunable selective reflection of circularly polarized light
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Poly(quinoxaline-2,3-diyl)s bearing (S)-2-methylbutyl, n-butyl, and 8-chlorooctyl groups as side chains were synthesized to fabricate dry solid polymer thin films. These films exhibited selective reflection of right-handed circular polarized light (CPL) in the visible region after annealing in CHCl3 vapor at room temperature. The handedness of reflected CPL was inverted to the left after annealing in 1,2-dichloroethane vapor. It was also found that the color of a particular single film along with the handedness of reflected CPL were fully tuned reversibly, upon exposure of the film to the vapor of various mixtures of chloroform and 1,2-dichloroethane in different ratios.
- Nagata, Yuuya,Takagi, Keisuke,Suginome, Michinori
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supporting information
p. 9858 - 9861
(2014/08/05)
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- Lengthening alkyl spacers to increase SBA-15-anchored Rh-P complex activities in 1-octene hydroformylation
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The alkyl spacer was lengthened in heterogenizing a Rh-P complex into mesoporous silicate SBA-15 to increase the immobilized catalyst activities in 1-octene hydroformylation. The Royal Society of Chemistry.
- Zhou, Wei,He, Dehua
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supporting information; experimental part
p. 5839 - 5841
(2009/04/13)
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- Synthesis of anacardic acids, 6-[8(Z),11(Z)-pentadecadienyl]salicylic acid and 6-[8(Z),11(Z),14-pentadecatrienyl]salicylic acid
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11-Chloro-3-methoxy-2-undecenal was synthesized from 8-bromooctanol, and an annelation reaction with this aldehyde and ethyl acetoacetate proceeded to give the ethyl 6-(8-chlorooctyl)salicylate. Ethyl 6-(8-chlorooctyl)salicylate was converted to ethyl 6-(7-formylheptyl)-2-methoxybenzoate through the iodide after protection of the phenolic hydroxyl group. Finally, the Wittig reaction with the aldehyde and triphenylphosphonium iodides in the presence of BuLi gave the methoxybenzoates, and then treatments of these methoxybenzoates with BBr3 in CH2Cl2 and 10% NaOH in ethanol gave 6-[8(Z),11(Z)-pentadecadienyl]salicylic acid (anacardic acid 3) and 6-[8(Z),11(Z),14-pentadecatrienyl]salicylic acid (anacardic acid 4) which were isolated from plants of the anacardiaceae.
- Satoh,Takeuchi,Nishimura,Ohta,Tobinaga
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- Process for the preparation of α-bromo, ω-chloroalkanes
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Described is a process for easily preparing an α-bromo,ω-chloroalkane which is high in purity represented by the formula: Br(CH2)n Cl in which n stands for an integer of 4 to 12. The process comprises reacting in an organic solvent an α,ω-dichloroalkane with an αω-dibromoalkane. As the organic solvent, an aprotic nitrogen-containing or sulfur-containing organic solvent having a dielectric constant at 20° C. of 20 or larger, for example, N,N-dimethylformamide, N,N-dimethylacetamide or N,N-dimethylimidazolidinone is preferred.
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- Enantioselective Total Synthesis of Harmonine, a Defence Alkaloid of Ladybugs (Coleoptera: Coccinellidae)
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An efficient and highly enantioselective (ee > 97percent) total synthesis of the ladybug defence alkaloid (17R,9Z)-1,17-diaminooctadec-9-ene in good overall yield is described.As the key step for the generation of the stereogenic center, asymmetric C-C bond formation by nucleophilic addition of methyllithium to an aldehyde SAMP hydrazone is used. Key Words: (17R,9Z)-1,17-Diaminooctadec-9-ene / Harmonine / Ladybug / SAMP hydrazone
- Enders, Dieter,Bartzen, Dominika
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p. 569 - 574
(2007/10/02)
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- DESIGN AND REACTIVITY OF ORGANIC FUNCTIONAL GROUPS - 2-PYRIDYLSULFONATES AS NUCLEOFUGAL ESTERS: REMARKABLY MILD TRANSFORMATIONS INTO HALIDES AND OLEFINS
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The novel 2-pyridylsulfonate esters are excellent leaving groups for the preparation of bromides and olefins under very mild reaction conditions.Displacements occur with inversion of configuration.
- Hanessian, Stephen,Kagotani, Masahiro,Komaglou, Kossi
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p. 1115 - 1120
(2007/10/02)
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