排序方式: 共有48条查询结果,搜索用时 31 毫秒
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Isabelle Pennequin Jenny Meyer Isabelle Suisse Andr Mortreux 《Journal of molecular catalysis. A, Chemical》1997,120(1-3):139-142
Sucrose-butadiene telomerization is efficiently carried out in water or water-organic medium in the presence of a palladium salt and TPPTS (TPPTS = trisodium tris(m-sulfonatophenyl)phosphine as catalyst. Mono- and dioctadienylether compounds are selectively obtained using a NaOH 1 M/isopropanol mixture. 相似文献
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Michaël Terrier Marc Visseaux Thomas Chenal André Mortreux 《Journal of polymer science. Part A, Polymer chemistry》2007,45(12):2400-2409
Neodymium trisborohydride, associated with MgR2 alkylating agents, affords an efficient initiator for the stereospecific polymerization of isoprene. This system presents good activity (150 kg of polyisoprene/mol of Nd/h; 95% yield in 2 h) and is trans-stereospecific (up to 97.7%), and its polymerization shows a quasi-living character. The molecular weights are controlled by the [Isoprene]/[Nd] ratio, with a polydispersity index lower than 1.6. A full study is presented here, including the influence of the nature of the alkylating reagent (MgR2), the solvent, the reaction temperature, the [MgR2]/[Nd] ratio, and the replacement of neodymium by other lanthanides. This work also includes a kinetic study of the system and a detailed NMR study of the microstructure of the trans-polyisoprene obtained, providing mechanistic insights about the polymerization reaction. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2400–2409, 2007 相似文献
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Andreia Valente Philippe Zinck André Mortreux Marc Visseaux 《Journal of polymer science. Part A, Polymer chemistry》2011,49(7):1615-1620
A series of lanthanum and neodymium borohydrido complexes comprising the trisborohydrides Nd(BH4)3(THF)3 ( 1a ) and La(BH4)3(THF)3 ( 1b ) and the half‐lanthanidocenes Cp*Nd(BH4)2(THF)2 ( 2a ) (Cp* = C5Me5) and Cp*La(BH4)2(THF)2 ( 2b ) has been assessed for the chain transfer copolymerization of isoprene and styrene. A transmetalation process is occurring efficiently with the borohydride complexes in the presence of magnesium dialkyl. The transmetalation is accompanied by (i) a gradual decrease of the 1,4‐trans stereoselectivity of the reaction at the benefit of 3,4‐selectivity and (ii) an increase in the quantity of styrene inserted in the copolymer. This can be at least partially attributed to a magnesium induced co‐oligomerization of isoprene and styrene. By combining dialkylmagnesium and trialkylaluminum, a 1,4‐trans stereospecific reversible coordinative chain transfer copolymerization of isoprene and styrene is observed when the half‐lanthanocene 2b is used as precatalyst. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
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Chiral Ligands Derived from Monoterpenes: Application in the Synthesis of Optically Pure Secondary Alcohols via Asymmetric Catalysis 下载免费PDF全文
Dr. Mohammed Samir Ibn El Alami Prof. Dr. Mohamed Amin El Amrani Dr. Francine Agbossou‐Niedercorn Dr. Isabelle Suisse Prof. Dr. André Mortreux 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(4):1398-1413
The preparation of optically pure secondary alcohols in the presence of catalysts based on chiral ligands derived from monoterpenes, such as pinenes, limonenes and carenes, is reviewed. A wide variety of these ligands has been synthesized and used in several catalytic reactions, including hydrogen transfer, C?C bond formation via addition of organozinc compounds to aldehydes, hydrosilylation, and oxazaborolidine reduction, leading to high activities and enantioselectivities. 相似文献
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Yong Miao Yupin Phuphuak Cyril Rousseau Till Bousquet André Mortreux Suwabun Chirachanchai Philippe Zinck 《Journal of polymer science. Part A, Polymer chemistry》2013,51(10):2279-2287
Binaphthyl‐diyl hydrogen phosphate has been assessed for the first time as a catalyst for the ring‐opening polymerization of ε‐caprolactone (CL) and δ‐valerolactone (VL). In the presence of benzyl alcohol as coinitiator at 40–60 °C, the polymerization is quantitative and controlled both in terms of dispersity and of number‐average molecular weight corresponding to the monomer/initiator ratio. The use of a selectively protected D ‐glucose derivative bearing the primary C6 hydroxyl group as initiator leads to the quantitative end‐functionalization of the polyesters in rather short reaction times (ca. 10 min at 60 °C for δ‐VL) with dispersities around 1.08–1.10. Methyl‐α‐D ‐glucopyranoside has been used as a carbohydrate polyol initiator in bulk. The initiation efficiency is partial, leading to hydrophilic carbohydrates functionalized polylactones in a one‐step procedure. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
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We prove a convergence acceleration result by theE-algorithm for sequences whose error has an asymptotic expansion on the scale of comparison for which a determinantal relation holds. This result is generalized to the vector case. Moreover we prove a result which contains an acceleration property for columns and diagonals of theE array. This result is applied to some alternating series. 相似文献
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