- A Change from Kinetic to Thermodynamic Control Enables trans-Selective Stereochemical Editing of Vicinal Diols
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Here, we report the selective, catalytic isomerization of cis-1,2-diols to trans-diequatorial-1,2-diols. The method employs triphenylsilanethiol (Ph3SiSH) as a catalyst and proceeds under mild conditions in the presence of a photoredox catalyst and under
- Gu, Xin,Wendlandt, Alison E.,Zhang, Yu-An
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supporting information
p. 599 - 605
(2022/01/03)
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- Novel Versatile Synthesis of Substituted Tetrabenzoporphyrins
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A novel general synthetic route to tetraaryltetrabenzoporphyrins (Ar 4TBP) with various peripheral functional groups is developed. The procedure includes (i) Barton-Zard condensation of 1-nitro- or 1-phenylsulfonylcyclohexenes with isocyanoacet
- Finikova, Olga S.,Cheprakov, Andrei V.,Beletskaya, Irina P.,Carroll, Patrick J.,Vinogradov, Sergei A.
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p. 522 - 535
(2007/10/03)
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- Electrochemical Coupling of Activated Olefins and Alkyl Dihalides: Formation of Cyclic Compounds
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The electrochemical coupling of dimethyl maleate, methyl cinnamate, 4-phenyl-3-buten-2-one, or methyl acrylate with dibromomethane, 1,3-dibromopropane, 1,4-dibromobutane or other substituted alkyl dihalogenides gave satisfactory yields of cyclic products.The reactions were performed in an undivided cell fitted with a sacrificial aluminum anode, in N-methylpyrrolidone (NMP), at constant current, and at room temperature.The role of the anodically generated metallic ions in this cyclocondensation has been evidenced.
- Lu, Yu-Wei,Nedelec, Jean-Yves,Folest, Jean-Claude,Perichon, Jacques
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p. 2503 - 2507
(2007/10/02)
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- STEREOCHEMICAL STUDIES 83. SATURATED HETEROCYCLES 76. PREPARATION AND CONFORMATIONAL STUDY OF PARTIALLY SATURATED 3,1-BENZOXAZINES, 3,1-BENZOXAZIN-2-ONES AND 3,1-BENZOXAZINE-2-THIONES
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The cis- and trans-2-amino-4-cyclohexene-1-carboxylic acids 1 and 3 react with imidates to give the condensed-skeleton, bicyclic cis- and trans-pyrimidin-4-ones 8 and 9.The amino acids 1 and 3 were reduced to the cis- and trans-1,3-aminoalcohols 6 and 7, which were cyclized by means of imidates to the bicyclic tetrahydro-4H-3,1-benzoxazines 10 and 11, or were converted, via the corresponding carbamates 14 and 15 into the tetrahydro-4H-3,1-benzoxazin-2(1H)-ones 16 and 17.The 2-thioxo analogues 18 and 19 were prepared by cyclization of the dithiocarbamates obtained from the aminoalcohols 6 and 7 by treatment with carbon disulphide.The trans-aminoalcohol 7 and its saturated analogue reacted with p-chlorobenzaldehyde to furnish the hexahydro 13 and octahydro-4H-3,1-benzoxazine 13a, respectively. 1H and 13C NMR studies showed that, similarly to the earlier-investigated analogues containing oxygen or unsubstituted nitrogen at position 1, the synthesized cis isomers 8, 10, 16 and 18 occurred as the preferred conformer in the heterocyclic twist inverse form of N-inside type (quasiaxal C6-N bond) (B).In the trans isomers containing a saturated C-2 atom (13 and 13a), H-2 and H-6 are in cis relative positions.
- Bernath, Gabor,Stajer, Geza,Szabo, Angela E.,Fueloep, Ferenc,Sohar, Pal
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p. 1353 - 1366
(2007/10/02)
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