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Mitsuji Yamashita - One of the best experts on this subject based on the ideXlab platform.
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A novel synthesis of amino acid derivatives of phospholene oxides
Tetrahedron Letters, 2004Co-Authors: Buchammagari Haritha, Masaki Takahashi, Valluru Krishna Reddy, Mitsuji YamashitaAbstract:Abstract A convenient synthetic approach is established to prepare a new class of 1- l -α-amino acid derivatives of phospholene oxides by amination of (±)-1-chloro-2-phospholene-1-oxides with several optically pure l -α-amino acid esters. All compounds obtained as a diastereomeric mixture in good to high yields. The two diastereomers were successfully separated by column chromatography and structurally identified by their spectral analyses.
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synthesis and characterization of the novel l substituted phenoxy phenyl 2 phospholene and Phospholane 1 oxide derivatives
Journal of Heterocyclic Chemistry, 2002Co-Authors: Valluru Krishna Reddy, Tatsuo Oshikawa, Lakonda Nagaprasada Rao, Masaki Takahashi, Junichi Onogawa, Mitsuji YamashitaAbstract:The synthesis of the novel 1-(substituted phenoxy/phenyl)-2-phospholene and Phospholane 1-oxide derivatives, which are analogs of sugars having a phosphorus atom in place of the ring oxygen of normal sugars, is described. All of the synthesized derivatives are structurally characterized by multi nuclear NMR, mass, and IR spectral data, elemental and X-ray crystallographic analyses.
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Synthesis and characterization of the novel l-(substituted phenoxy/phenyl)-2-phospholene and Phospholane 1-oxide derivatives
Journal of Heterocyclic Chemistry, 2002Co-Authors: Valluru Krishna Reddy, Tatsuo Oshikawa, Onogawa Junichi, Lakonda Nagaprasada Rao, Masaki Takahashi, Mitsuji YamashitaAbstract:The synthesis of the novel 1-(substituted phenoxy/phenyl)-2-phospholene and Phospholane 1-oxide derivatives, which are analogs of sugars having a phosphorus atom in place of the ring oxygen of normal sugars, is described. All of the synthesized derivatives are structurally characterized by multi nuclear NMR, mass, and IR spectral data, elemental and X-ray crystallographic analyses.
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Novel Synthesis and Structures of Amines and Triazole-Derived Glycoside and Nucleoside Derivatives of Phosphanyl Sugar Analogs
Journal of Carbohydrate Chemistry, 1999Co-Authors: Mitsuji Yamashita, Kazumitsu Suzuki, Yukihiro Kato, Akihito Iida, Koichi Ikai, Putta Mallikarjuna Reddy, Tatsuo OshikawaAbstract:ABSTRACT 3-Methyl-1-phenyl-2-phospholene and 1-phenyl-2-phospholene 1-oxides were converted into 2-bromo-3-hydroxy-3-methyl-1-phenylPhospholane and 2-bromo-3-hydroxy-1-phenylPhospholane 1-oxide (1-bromo-1,3,4-trideoxy-1,4-C-[(R, S)-phenylphosphinylidene]-glycero-tetrofuranose) by the action of bromine in aqueous medium. The bromo substituent of the Phospholane was substituted by treatment with amines or an azide anion to afford novel glycoside derivatives of phosphanyl sugar analogs such as 2-amino-3-hydroxy-1-phenylPhospholane (3,4-dideoxy-1,4-C-[(R, S)-phenylphosphinylidene]-glycero-tetrofuranosylamine) and 2-azido-3-hydroxy-3-methyl-1-phenylPhospholane 1-oxides with retention of the configuration. The 1,3-dipolar cycloaddition of the 2-azido derivative of the Phospholane with alkynes gave 3-hydroxy-3-methyl-1-phenyl-2-(triazol-1′-y1)Phospholane 1-oxides as a novel triazole-derived nucleoside of phosphanyl sugar analogs. The structure of the glycoside and nucleoside derivatives of the phosphanyl sugar a...
Sunetra Deshmukh - One of the best experts on this subject based on the ideXlab platform.
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Phospholane-Catalyzed Wittig Reaction.
ChemInform, 2015Co-Authors: Thomas Werner, Marcel Hoffmann, Sunetra DeshmukhAbstract:Isophosphindoline P-oxide (PIO) is a suitable and potentially tunable catalyst for the Wittig reaction of aldehydes with activated organohalides.
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Phospholane catalyzed wittig reaction
European Journal of Organic Chemistry, 2015Co-Authors: Thomas Werner, Marcel Hoffmann, Sunetra DeshmukhAbstract:We identified 2-phenylisophosphindoline 2-oxide as a suitable and potentially tunable catalyst for the catalytic Wittig reaction of aldehydes with activated organohalides. This catalyst was obtained by a straightforward two-step synthesis. Trimethoxysilane proved to be an efficient reducing agent for the in situ generation and regeneration of the catalyst from the corresponding phosphane oxide. Sodium carbonate was identified as a suitable base for the transformation. It is note
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Phospholane‐Catalyzed Wittig Reaction
European Journal of Organic Chemistry, 2015Co-Authors: Thomas Werner, Marcel Hoffmann, Sunetra DeshmukhAbstract:We identified 2-phenylisophosphindoline 2-oxide as a suitable and potentially tunable catalyst for the catalytic Wittig reaction of aldehydes with activated organohalides. This catalyst was obtained by a straightforward two-step synthesis. Trimethoxysilane proved to be an efficient reducing agent for the in situ generation and regeneration of the catalyst from the corresponding phosphane oxide. Sodium carbonate was identified as a suitable base for the transformation. It is note
Valluru Krishna Reddy - One of the best experts on this subject based on the ideXlab platform.
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A novel synthesis of amino acid derivatives of phospholene oxides
Tetrahedron Letters, 2004Co-Authors: Buchammagari Haritha, Masaki Takahashi, Valluru Krishna Reddy, Mitsuji YamashitaAbstract:Abstract A convenient synthetic approach is established to prepare a new class of 1- l -α-amino acid derivatives of phospholene oxides by amination of (±)-1-chloro-2-phospholene-1-oxides with several optically pure l -α-amino acid esters. All compounds obtained as a diastereomeric mixture in good to high yields. The two diastereomers were successfully separated by column chromatography and structurally identified by their spectral analyses.
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Synthesis and characterization of the novel l-(substituted phenoxy/phenyl)-2-phospholene and Phospholane 1-oxide derivatives
Journal of Heterocyclic Chemistry, 2002Co-Authors: Valluru Krishna Reddy, Tatsuo Oshikawa, Onogawa Junichi, Lakonda Nagaprasada Rao, Masaki Takahashi, Mitsuji YamashitaAbstract:The synthesis of the novel 1-(substituted phenoxy/phenyl)-2-phospholene and Phospholane 1-oxide derivatives, which are analogs of sugars having a phosphorus atom in place of the ring oxygen of normal sugars, is described. All of the synthesized derivatives are structurally characterized by multi nuclear NMR, mass, and IR spectral data, elemental and X-ray crystallographic analyses.
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synthesis and characterization of the novel l substituted phenoxy phenyl 2 phospholene and Phospholane 1 oxide derivatives
Journal of Heterocyclic Chemistry, 2002Co-Authors: Valluru Krishna Reddy, Tatsuo Oshikawa, Lakonda Nagaprasada Rao, Masaki Takahashi, Junichi Onogawa, Mitsuji YamashitaAbstract:The synthesis of the novel 1-(substituted phenoxy/phenyl)-2-phospholene and Phospholane 1-oxide derivatives, which are analogs of sugars having a phosphorus atom in place of the ring oxygen of normal sugars, is described. All of the synthesized derivatives are structurally characterized by multi nuclear NMR, mass, and IR spectral data, elemental and X-ray crystallographic analyses.
Armin Börner - One of the best experts on this subject based on the ideXlab platform.
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Chiral P-chloroPhospholane : A versatile building block for the synthesis of ligands
Synlett, 2007Co-Authors: Jens Holz, Axel Monsees, Renat Kadyrov, Armin BörnerAbstract:The synthesis of enantiomerically pure (R,R)-1-chloro-2,5-dimethylPhospholane is described, which can be used for the synthesis of a wide range of phosphine ligands bearing a Phospholane moiety.
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New chiral monodentate Phospholane ligands by highly stereoselective hydrophosphination
Tetrahedron: Asymmetry, 2006Co-Authors: Vitaliy A. Bilenko, Anke Spannenberg, Wolfgang Baumann, Igor V. Komarov, Armin BörnerAbstract:Abstract New chiral Phospholanes 6 were prepared in both enantiomeric forms starting from l - and d -tartaric acid. The key step in the synthetic sequence is the double hydrophosphination of unsaturated chiral bis(lactone) 9 by NaPhPH(BH 3 ). This method was used for the first time in the formation of chiral Phospholanes. The structure of Phospholane 6a was confirmed by X-ray crystallography. σ-Donor properties of the Phospholanes were estimated by measurement of 1 J ( 31 P– 77 Se) coupling constants in the corresponding phosphine selenides. The new Phospholanes were tested as ligands in the Rh-catalyzed enantioselective hydrogenation of functionalized standard olefins (65–92% ee).
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Synthesis of Chiral 2,5‐Bis(oxymethyl)‐Functionalized Bis(Phospholanes) and Their Application in Rh‐ and Ru‐Catalyzed Enantioselective Hydrogenations
European Journal of Organic Chemistry, 2001Co-Authors: Jens Holz, Rainer Stürmer, Ute Schmidt, Hans-joachim Drexler, Detlef Heller, Hans-peter Krimmer, Armin BörnerAbstract:The synthesis of a series of chiral 2,5-bis(oxymethyl)-substituted bis(Phospholanes) 13a−c and 15a,b (BASPHOS) is described, representing functionalized derivatives of the prominent DuPHOS or BPE ligands. D-Mannitol was used as the starting material for these ligands. New bisPhospholanes were used as ligands in the enantioselective rhodium(I)-catalyzed hydrogenation of functionalized olefins like unsaturated α- and β-amino acid derivatives, itaconates, and an unsaturated phosphonate. A relevant ruthenium(II) catalyst was used for the reduction of prochiral β-oxo esters. The enantioselectivities, ranging from 8−99% ee, were strongly dependent on the type of the substituent on the oxymethyl group as well on the bridge connecting the Phospholane units.
Usein M. Dzhemilev - One of the best experts on this subject based on the ideXlab platform.
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Aluminacyclopentanes in the synthesis of 3-substituted Phospholanes and α,ω-bisPhospholanes.
Beilstein journal of organic chemistry, 2016Co-Authors: Vladimir A. D’yakonov, Alevtina L. Makhamatkhanova, Rina A. Agliullina, Leisan K. Dil’mukhametova, Tatyana V. Tyumkina, Usein M. DzhemilevAbstract:An efficient one-pot process for the synthesis of 3-substituted Phospholanes and α,ω-bisPhospholanes was developed. The method involves the replacement of aluminium in aluminacyclopentanes, prepared in situ by catalytic cycloalumination of α-olefins and α,ω-diolefins, by phosphorus atoms on treatment with dichlorophosphines (R′PCl2). Hydrogen peroxide oxidation and treatment with S8 of the synthesized Phospholanes and α,ω-bisPhospholanes afforded the corresponding 3-alkyl(aryl)-1-alkyl(phenyl)Phospholane 1-oxides, 3-alkyl(aryl)-1-alkyl(phenyl)Phospholane 1-sulfides, bisPhospholane 1,1'-dioxides, and bisPhospholane 1,1'-disulfides in nearly quantitative yields. The complexes LMo(CO)5 (L = 3-hexyl-1-phenylPhospholane, 3-benzyl-1-methylPhospholane, 1,2-bis(1-phenylphospholan-3-yl)ethane, and 1,6-bis(1-phenylphospholan-3-yl)hexane were prepared by the reaction of 3-substituted Phospholanes and α,ω-bisPhospholanes with molybdenum hexacarbonyl. The structure of the complexes was proved by multinuclear 1H, 13C, and 31P spectroscopy.
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Catalytic Cycloalumination for the Synthesis of Norbornane-Annulated Phospholanes
2015Co-Authors: V. A. D’yakonov, T. V. Tyumkina, Alevtina L. Makhamatkhanova, Rina A. Agliullina, Leisan K. Dilmukhametova, Usein M. DzhemilevAbstract:An effective one-pot method for the synthesis of polycyclic Phospholanes by in situ reaction of dichlorophosphines (RPCl2, where R = Ph, t-Bu, Me) with norbornane-annulated aluminacyclopentanes was obtained by catalytic cycloalumination of norbornenes. Oxidation of Phospholanes gave the corresponding polycyclic Phospholane 3-oxides (3-sulfides). The molybdenum complex L2Mo(CO)4 (L = 3-phenyl-3-phosphatricyclo[5.2.1.02,6]decane) was prepared for the first time by the reaction of 3-phenyl-3-phosphatricyclo[5.2.1.02,6]decane with molybdenum hexacarbonyl. The structures of the obtained compounds were confirmed by X-ray diffraction and multinuclear 1H, 13C, and 31P NMR spectroscopy
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Catalytic Cycloalumination for the Synthesis of Norbornane-Annulated Phospholanes
Organometallics, 2014Co-Authors: Vladimir A. D’yakonov, Alevtina L. Makhamatkhanova, Rina A. Agliullina, Leisan K. Dil’mukhametova, Tatyana V. Tyumkina, Usein M. DzhemilevAbstract:An effective one-pot method for the synthesis of polycyclic Phospholanes by in situ reaction of dichlorophosphines (RPCl2, where R = Ph, t-Bu, Me) with norbornane-annulated aluminacyclopentanes was obtained by catalytic cycloalumination of norbornenes. Oxidation of Phospholanes gave the corresponding polycyclic Phospholane 3-oxides (3-sulfides). The molybdenum complex L2Mo(CO)4 (L = 3-phenyl-3-phosphatricyclo[5.2.1.02,6]decane) was prepared for the first time by the reaction of 3-phenyl-3-phosphatricyclo[5.2.1.02,6]decane with molybdenum hexacarbonyl. The structures of the obtained compounds were confirmed by X-ray diffraction and multinuclear 1H, 13C, and 31P NMR spectroscopy.