154026-89-8Relevant academic research and scientific papers
Fully substituted pyranones via quasi-heterogeneous genuinely ligand-free migita-stille coupling of iodoacrylates
Kratochv??l, Ji????,Nov??k, Zden??k,Ghavre, Mukund,Nov??kov??, Lucie,R????i??ka, Ale??,Kune??, Ji????,Pour, Milan
supporting information, p. 520 - 523 (2015/03/04)
Migita-Stille coupling of (Z)-?2-iodoacrylates with (E)-?±-stannyl allylic alcohols to furnish 5-alkylidene-4-substituted-5,6-dihydro-2H-pyran-2-ones is efficiently catalyzed by 2% Pd black in DMF, while Pd(PPh3)4 is inactive. Heterogeneous Pd released in solution is most likely responsible for the catalysis. The reaction is applicable to other substrates, without having to resort to ligands, additives, and/or solid support for Pd. The resulting pyranones can be rearranged to fully functionalized pyranones in another single step.
Palladium-catalyzed stereoretentive olefination of unactivated C(sp3)-H bonds with vinyl iodides at room temperature: Synthesis of β-vinyl α-amino acids
Wang, Bo,Lu, Chengxi,Zhang, Shu-Yu,He, Gang,Nack, William A.,Chen, Gong
supporting information, p. 6260 - 6263 (2015/02/19)
A method is reported for palladium-catalyzed N-quinolyl carboxamide-directed olefination of the unactivated C(sp3)-H bonds of phthaloyl alanine with a broad range of vinyl iodides at room temperature. This reaction represents the first example of the stereoretentive installation of multisubstituted terminal and internal olefins onto unactivated C(sp3)-H bonds. These methods enable access to a wide range of challenging β-vinyl α-amino acid products in a streamlined and controllable fashion, beginning from simple precursors.
α-(N-carbamoyl)alkylcuprate chemistry in the synthesis of nitrogen heterocycles
Dieter, R. Karl,Lu, Kai
, p. 847 - 855 (2007/10/03)
The conjugate adducts obtained via coupling of α-(N-carbamoyl)alkylcuprates with α,β-ynoates, α-allenyl esters, or α,β-enoates or enimides undergo N-Boc deprotection and cyclization onto the ester functionality upon treatment with PhOH/TMSCl, catecholboron bromide, or trimethylsilyl triflate. This two-pot sequence provides synthetic routes to 4-alkylidinepyrrolidine-2-ones, 4-alkylidinepyrrolizidin-2-ones, and 4-alkylidineindolizidin-2-ones via allenyl esters; pyrrolin-2-ones, tetrahydropyrrolizin-2-ones, and tetrahydroindolizin-2-ones via α,β-ynoates; pyrrolidin-2-ones, pyrrolizidin-2-ones, and indolizidin-2-ones via α,β-enoates or α,β-enimides. The reluctance of γ-carbamoyl-α,β-enoates to undergo E/Z isomerization requires the use of (Z)-β-iodo-α,β-enoates readily prepared by the addition of HI to the alkynyl esters for the efficient preparation of pyrrolinones, tetrahydropyrrolizinones, and tetrahydroindolizinones. Utilization of ω-functionalized α,β-ynoates or β-iodo-α,β-enoates allows for cyclization onto the ω-functionality providing for a synthetic route to quinolizidines.
Synthesis of isocoumarins and α-pyrones via palladium-catalyzed annulation of internal alkynes
Larock, Richard C.,Doty, Mark J.,Han, Xiaojun
, p. 8770 - 8779 (2007/10/03)
A number of 3,4-disubstituted isocoumarins and polysubstituted α- pyrones have been prepared in good yields by treating halogen- or triflate- containing aromatic and α,β-unsaturated esters, respectively, with internal alkynes in the presence of a palladiu
Stereoselective Hydroiodination of 3-Substituted Derivatives of Propynoic Acid
Luo, Fen-Tair,Hsieh, Li-Chen
, p. 871 - 873 (2007/10/03)
The hydroiodination of 3-substituted propynoic acids and their derivatives with sodium iodide/trimethylsilyl chloride/water in acetonitrile at 25 deg C gives stereoselectively (Z)-3-iodopropenoic acid derivatives in good yields. - Keywords: 3-Substituted-
