1504-74-1Relevant articles and documents
Stabilization and activation of unstable propynal in the zeolite nanospace and its application to addition reactions
Hayashi, Daijiro,Igura, Yuta,Masui, Yoichi,Onaka, Makoto
, p. 4422 - 4430 (2017)
Propynal (HC≡C-CHO), having both a C≡C triple bond and a formyl group in a molecule, is a promising building block but its labile property to easily polymerize often narrows its application for organic synthesis. In a similar way to unstable molecules, such as formaldehyde and acrolein, propynal is also stabilized and remains unchanged in supercages of Na-Y zeolite for over 30 days at ambient temperature. There, the carbonyl oxygen atoms of propynal coordinate to sodium ions in Na-Y which was proved by a 13C-DD/MAS-NMR analysis. In addition, propynal adsorbed in zeolite is sufficiently activated to allow unprecedented reactions; i.e., (1) a 1,3-dipolar cycloaddition with electron-deficient α-diazocarbonyl compounds, (2) a 1,4-addition with mono-, di-, and trimethoxy-substituted benzenes, and (3) a [2 + 2] cycloaddition of unactivated cycloalkenes. The nanospace of the zeolites keeps the products from dimerization during reaction (1) and from successive side-reactions in reaction (2). Quantum chemical calculations demonstrated that reaction (3) proceeds via a one-step-like non-concerted mechanism to afford the corresponding [2 + 2] cycloadducts. These three reactions can produce valuable synthetic intermediates retaining both a formyl group and a C=C double bond.
Method for preparing olefine aldehyde by catalyzing terminal alkyne or terminal conjugated eneyne and diphosphine ligand used in method
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Paragraph 0149-0154, (2021/05/29)
The invention discloses a method for preparing olefine aldehyde by catalyzing terminal alkyne or terminal conjugated eneyne and a diphosphine ligand used in the method. According to the invention, indole-substituted phosphoramidite diphosphine ligand which is stable in air and insensitive to light is synthesized by utilizing a continuous one-pot method, and the indole-substituted phosphoramidite diphosphine ligand and a rhodium catalyst are used for jointly catalyzing to successfully achieve a hydroformylation reaction of aromatic terminal alkyne and terminal conjugated eneyne under the condition of synthesis gas for the first time, so that an olefine aldehyde structure compound can be rapidly and massively prepared, and particularly, a polyolefine aldehyde structure compound which is more difficult to synthesize in the prior art can be easily prepared and synthesized, and a novel method is provided for synthesis and modification of drug molecules, intermediates and chemical products.
Highly Enantioselective Synthesis of Functionalized Glutarimide Using Oxidative N-Heterocyclic Carbene Catalysis: A Formal Synthesis of (?)-Paroxetine
Porey, Arka,Santra, Surojit,Guin, Joyram
, p. 5313 - 5327 (2019/04/16)
A simple yet highly effective approach toward enantioselective synthesis of trans-3,4-disubstituted glutarimides from readily available starting materials is developed using oxidative N-heterocyclic carbene catalysis. The catalytic reaction involves a formal [3 + 3] annulation between enals and substituted malonamides enabling the production of glutarimide derivatives in a single chemical operation via concomitant formation of C-C and C-N bonds. The reaction offers easy access to a broad range of functionalized glutarimides with excellent enantioselectivity and good yield. Synthetic application of the method is demonstrated via formal synthesis of (?)-paroxetine and other bioactive molecules.
