Cyclic Sulfites and Cyclic Sulfates: Epoxide like Synthons

Lohray, B. B.

doi:10.1055/s-1992-26295

Cited by 234 publications

(77 citation statements)

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“…[18] The intermediate sulfate (not shown) was hydrolyzed with aqueous sulfuric acid to the 2-azido-3-hydroxy diester (À)-15. This sequence has been described by Shao and Goodman for the preparation of 2-amino-3-hydroxy acids.…”

Section: Chemistrymentioning

confidence: 99%

Asymmetric Synthesis and Receptor Pharmacology of the Group II mGlu Receptor Ligand (1S,2R,3R,5R,6S)‐2‐Amino‐3‐hydroxy‐bicyclo[3.1.0]hexane‐2,6‐dicarboxylic Acid—HYDIA

et al. 2008

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The asymmetric synthesis and receptor pharmacology of (1S,2R,3R,5R,6S)-2-amino-3-Hydroxy-bicyclo[3.1.0]hexane-2,6-dicarboxylic Acid (+)-9 (HYDIA) and a few of its O-alkylated derivatives are described. The key step of the synthesis utilizes Sharpless' asymmetric dihydroxylation (AD-beta) for the kinetic resolution of a bicyclic racemic precursor olefin. In contrast to the bicyclic glutamate analogue LY354740, which is a potent and selective agonist for the group II metabotropic glutamate receptors (mGluRs), these new conformationally restricted and also hydroxylated or alkoxylated glutamate analogues are potent and selective antagonists for the group II mGluRs.

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Section: Chemistrymentioning

confidence: 99%

Asymmetric Synthesis and Receptor Pharmacology of the Group II mGlu Receptor Ligand (1S,2R,3R,5R,6S)‐2‐Amino‐3‐hydroxy‐bicyclo[3.1.0]hexane‐2,6‐dicarboxylic Acid—HYDIA

et al. 2008

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“…9,10 The 1 H-NMR spectra of compounds 13-16 have a known preference of the sulfite oxygen atom for the axial position. 12 This is manifested by a downfield shift of axial H-2 and H-4 protons and large diaxial coupling constants in 13 and 15 versus corresponding data found for 14 and 16 (see Experimental).…”

Section: Known Compoundmentioning

confidence: 99%

Six‐membered cyclic sulfites derived from glucofuranose and 1,2,4‐butanetriol

et al. 2001

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Six-membered cyclic sulfites derived from glucofuranose derivatives 5, 6 and from 1-O-tert-butyldimethylsilil-1,2,4-butanetriol 12 were synthesized and separated into pure diastereomers which were in turn subjected to the sequence of reactions leading to the introduction of the terminal vinyl ether fragment. Reactivity and applicability of cyclic sulfites as intermediates in [2+2]cycloaddition of chlorosulfonyl isocyanate (CSI) to vinyl ethers were studied. The cycloaddition to vinyl ethers 19 and 20 proceeded in low yield and low asymmetric induction, in the case of the former, and moderate yield and pronounced asymmetric induction, in the case of the latter. The (1)H-NMR spectra of sulfites 13-16 reveal a preference of the sulfite oxygen atom for the axial position. Thus, well-defined conformation in solution for compounds 13 and 15 and a mixture of the two possible chair forms for sulfites 14 and 16 could be assigned. The stretching frequency of the S-->O bond in stable conformation with an axial sulfite oxygen occurs in the range 1,160-1,210 cm(-1), whereas conformationally mobile sulfites exhibit corresponding absorption above 1,220 cm(-1). The absolute configuration assignments of sulfites 7, 8, 15, 16 and 25-28 were done empirically based on the combined analysis of the NMR, IR, X-ray, and dichroic data. It was demonstrated that the sign of the Cotton effect around 194 nm correlated with the absolute stereochemistry at the sulfur atom in a sulfite chromophore.

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“…[3,4] This process, however, produces stoichiometric amounts of the ammonium or pyridinium salts as waste. Additionally, chlorination of 1,2-diol by thionyl chloride generates chloride derivative by-products.…”

Section: Introductionmentioning

confidence: 99%

Synthesis of Cyclic Sulfites from Epoxides and Sulfur Dioxide with Silica‐Immobilized Homogeneous Catalysts

Takenaka

Kiyosu²,

Mori³

et al. 2011

ChemSusChem

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Quaternary ammonium- and amino-functionalized silica catalysts have been prepared for the selective synthesis of cyclic sulfites from epoxides and sulfur dioxide, demonstrating the effects of immobilizing the homogeneous catalysts on silica. The cycloaddition of sulfur dioxide to various epoxides was conducted under solvent-free conditions at 100 °C. The quaternary ammonium- and amino-functionalized silica catalysts produced cyclic sulfites in high yields (79-96 %) that are comparable to those produced by the homogeneous catalysts. The functionalized silica catalysts could be separated from the product solution by filtration, thereby avoiding the catalytic decomposition of the cyclic sulfite products upon distillation of the product solution. Heterogenization of a homogeneous catalyst by immobilization can, therefore, improve the efficiency of the purification of crude reaction products. Despite a decrease in catalytic activity after each recycling step, the heterogeneous pyridine-functionalized silica catalyst provided high yields after as many as five recycling processes.

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Cyclic Sulfites and Cyclic Sulfates: Epoxide like Synthons

Cited by 234 publications

References 0 publications

Asymmetric Synthesis and Receptor Pharmacology of the Group II mGlu Receptor Ligand (1S,2R,3R,5R,6S)‐2‐Amino‐3‐hydroxy‐bicyclo[3.1.0]hexane‐2,6‐dicarboxylic Acid—HYDIA

Asymmetric Synthesis and Receptor Pharmacology of the Group II mGlu Receptor Ligand (1S,2R,3R,5R,6S)‐2‐Amino‐3‐hydroxy‐bicyclo[3.1.0]hexane‐2,6‐dicarboxylic Acid—HYDIA

Six‐membered cyclic sulfites derived from glucofuranose and 1,2,4‐butanetriol

Synthesis of Cyclic Sulfites from Epoxides and Sulfur Dioxide with Silica‐Immobilized Homogeneous Catalysts

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