The Experts below are selected from a list of 2079 Experts worldwide ranked by ideXlab platform
Juyoung Yoon - One of the best experts on this subject based on the ideXlab platform.
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synthesis of large ring 3 4 alkylenedioxythiophenes adot derivatives via Mitsunobu Reaction
ChemInform, 2011Co-Authors: Joohee Kang, Fang Wang, Seungmin Paek, Seong Ju Hwang, Youngmee Kim, Sung Jin Kim, Jinho Choy, Juyoung YoonAbstract:Mitsunobu Reaction of dihydroxythiophene (I) with various diols provides an easy access to the title systems.
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synthesis of large ring 3 4 alkylenedioxythiophenes adot derivatives via Mitsunobu Reaction
Tetrahedron Letters, 2011Co-Authors: Joohee Kang, Fang Wang, Seungmin Paek, Seong Ju Hwang, Youngmee Kim, Sung Jin Kim, Jinho Choy, Juyoung YoonAbstract:Poly(3,4-ethylenedioxythiophene) (PEDOT) stands out for its optimized conductivity, stability, and high degree of transparency which has led to its successful commercialization. These excellent properties of PEDOT are mostly ascribed to the alkylenedioxy bridge across the 3- and 4-positions, and thus much effort has been dedicated to synthesizing 3,4-ethylenedioxythiophene (EDOT) analogs. However, only few homologous compounds were successfully synthesized, such as 3,4-propylenedioxythiophene (PrDOT) or 3,4-(1,4-butylenedioxy)thiophene (BuDOT). In this Letter, we use Mitsunobu Reaction to synthesize a series of 3,4-alkylenedioxythiophenes (ADOTs) derivatives with 8- to 16-membered rings. The eight-membered compounds were obtained in high or excellent yield. We also found that the 9- to 16-membered EDOT analogs were obtained in relatively low yield because of the competitive Reaction to make dimers. Our method provides an easy way to modify ethylenedioxythiophenes (EDOTs), and these obtained ADOTs compounds are promising building blocks for the synthesis of functional π-conjugated systems used in material chemistry.
K N Houk - One of the best experts on this subject based on the ideXlab platform.
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computational exploration of a redox neutral organocatalytic Mitsunobu Reaction
Journal of the American Chemical Society, 2020Co-Authors: Yike Zou, Jonathan J Wong, K N HoukAbstract:The mechanism of the redox-neutral organocatalytic Mitsunobu Reaction, catalyzed by (2-hydroxybenzyl)diphenylphosphine oxide, reported by Denton et al., has been studied computationally with ωB97X-...
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computational exploration of a redox neutral organocatalytic Mitsunobu Reaction
Journal of the American Chemical Society, 2020Co-Authors: Yike Zou, Jonathan J Wong, K N HoukAbstract:The mechanism of the redox-neutral organocatalytic Mitsunobu Reaction, catalyzed by (2-hydroxybenzyl)diphenylphosphine oxide, reported by Denton et al., has been studied computationally with ωB97X-D density functional theory. We discovered that the nucleophilic substitution Reaction between carboxylate and alkoxyphosphonium ions, to reform the phosphine oxide catalyst, is the rate-determining step of the overall process and is significantly accelerated compared with a general-acid-catalyzed SN2 Reaction. The (2-hydroxybenzyl)diphenylphosphine oxide is regenerated and activated in every catalytic cycle via intramolecular dehydration/cyclization. We also designed several phosphine oxide catalysts that we predict to be more effective catalysts.
Ross M Denton - One of the best experts on this subject based on the ideXlab platform.
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the catalytic Mitsunobu Reaction a critical analysis of the current state of the art
Organic and Biomolecular Chemistry, 2018Co-Authors: Rhydian H Beddoe, Helen F Sneddon, Ross M DentonAbstract:The Mitsunobu Reaction is widely regarded as the pre-eminent method for performing nucleophilic substitutions of alcohols with inversion of configuration. However, its applicability to large-scale synthesis is undermined by the fact that alcohol activation occurs at the expense of two stoichiometric reagents – a phosphine and an azodicarboxylate. The ideal Mitsunobu Reaction would be sub-stoichiometric in the phosphine and azodicarboxylate species and employ innocuous terminal oxidants and reductants to achieve recycling. This Review article provides a summary and analysis of recent advances towards the development of such catalytic Mitsunobu Reactions.
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development of a redox free Mitsunobu Reaction exploiting phosphine oxides as precursors to dioxyphosphoranes
Chemical Communications, 2014Co-Authors: Xiaoping Tang, Charlotte Chapman, Matthew Whiting, Ross M DentonAbstract:The development of the first redox-free protocol for the Mitsunobu Reaction is described. This has been achieved by exploiting triphenylphosphine oxide – the unwanted by-product in the conventional Mitsunobu Reaction – as the precursor to the active P(V) coupling reagent. Multinuclear NMR studies are consistent with hydroxyl activation via an alkoxyphosphonium salt.
Murray Goodman - One of the best experts on this subject based on the ideXlab platform.
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utilizing the intramolecular fukuyama Mitsunobu Reaction for a flexible synthesis of novel heterocyclic scaffolds for peptidomimetic drug design
Bioorganic & Medicinal Chemistry Letters, 2005Co-Authors: Christoph W Zapf, Juan R Del Valle, Murray GoodmanAbstract:Abstract We report the synthesis of the novel scaffolds pyrazino[1,2- b ]isoquinoline and pyrrolo[1,2- a ]pyrazine displaying the somatostatin pharmacophores. Both classes of compounds contain a pyrazine heterocycle, which can be prepared in a straightforward manner utilizing an intramolecular Fukuyama–Mitsunobu Reaction. As both the families derive from amino acids, they can be accessed in high optical purity.
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solid phase synthesis of amine bridged cyclic enkephalin analogues via on resin cyclization utilizing the fukuyama Mitsunobu Reaction
Journal of Organic Chemistry, 2002Co-Authors: Yosup Rew, Murray GoodmanAbstract:An efficient solid-phase synthetic route is described for the preparation of 13-membered amine-bridged cyclic enkephalin analogues (ABEs) 1a and 1c-1j (Figure 1) resulting from a sulfonamide-containing peptide whose backbone is bound to a resin. The Fukuyama-Mitsunobu Reaction of the 2-nitrobenzenesulfonyl-protected amine bound to the solid support with protected aminoethanol in the presence of triphenylphosphine and diisopropyl azodicarboxylate (DIAD) is utilized to prepare a resin-bound sulfonamide-protected secondary amine. After peptide cyclization, this protected amine functionality becomes the "amine bridge" of the target molecule. In addition, the reagent DIAD was found to be a superior reagent compared to diethyl azodicarboxylate (DEAD) in the solid-phase Fukuyama-Mitsunobu Reaction.
Joohee Kang - One of the best experts on this subject based on the ideXlab platform.
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synthesis of large ring 3 4 alkylenedioxythiophenes adot derivatives via Mitsunobu Reaction
ChemInform, 2011Co-Authors: Joohee Kang, Fang Wang, Seungmin Paek, Seong Ju Hwang, Youngmee Kim, Sung Jin Kim, Jinho Choy, Juyoung YoonAbstract:Mitsunobu Reaction of dihydroxythiophene (I) with various diols provides an easy access to the title systems.
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synthesis of large ring 3 4 alkylenedioxythiophenes adot derivatives via Mitsunobu Reaction
Tetrahedron Letters, 2011Co-Authors: Joohee Kang, Fang Wang, Seungmin Paek, Seong Ju Hwang, Youngmee Kim, Sung Jin Kim, Jinho Choy, Juyoung YoonAbstract:Poly(3,4-ethylenedioxythiophene) (PEDOT) stands out for its optimized conductivity, stability, and high degree of transparency which has led to its successful commercialization. These excellent properties of PEDOT are mostly ascribed to the alkylenedioxy bridge across the 3- and 4-positions, and thus much effort has been dedicated to synthesizing 3,4-ethylenedioxythiophene (EDOT) analogs. However, only few homologous compounds were successfully synthesized, such as 3,4-propylenedioxythiophene (PrDOT) or 3,4-(1,4-butylenedioxy)thiophene (BuDOT). In this Letter, we use Mitsunobu Reaction to synthesize a series of 3,4-alkylenedioxythiophenes (ADOTs) derivatives with 8- to 16-membered rings. The eight-membered compounds were obtained in high or excellent yield. We also found that the 9- to 16-membered EDOT analogs were obtained in relatively low yield because of the competitive Reaction to make dimers. Our method provides an easy way to modify ethylenedioxythiophenes (EDOTs), and these obtained ADOTs compounds are promising building blocks for the synthesis of functional π-conjugated systems used in material chemistry.