Ni(0)–Cu(i): a powerful combo catalyst for simultaneous coupling and cleavage of the C–N bond with cyclization to valuable amide-based pyrroles and 4-pyridones
An efficient method for the construction of polysubstituted 4-pyridones via self-condensation of β-keto amides mediated by P<sub>2</sub>O<sub>5</sub> and catalyzed by zinc bromide
作者:Liquan Tan、Peng Zhou、Cui Chen、Weibing Liu
DOI:10.3762/bjoc.9.304
日期:——
is presented for the synthesis of polysubstituted 4-pyridones and 2-pyridones from beta-keto amides. A variety of beta-keto amides are used in this approach, and a wide range of functionalized 4-pyridones and 2-pyridones were obtained in good to excellent yields. When employing the N-aryl beta-keto amides as the substrates in this protocol, 4-pyridones are resulted, however, when using N-aliphatic-substituted
Abstract An alternative convenient approach for the bromination of various poly-substituted 4-pyridones has been developed via an oxidative nuclear bromination in the presence of sole pyridinium bromochromate (PBC). The PBC performs the dual role of oxidant and source of Br+ during the process. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic
Mediated by sodium persulfate (Na(2)S(2)0(8)), a series of polysubstituted 4-pyridones were synthesized via self-condensation of N-aryl acetoacetamides, during which a novel N to C 1,3-acyl migration should be involved. The structure of 4-pyridone was unequivocally confirmed by X-ray diffraction analysis. However, the self-condensation of N-benzyl acetoacetamides under the same condition gave polysubstituted 2-pyridones instead of 4-pyridones.
PIERCE, J. B.;ARIYAN, Z. S.;OVENDEN, G. S., J. MED. CHEM., 1982, 25, N 2, 131-136
作者:PIERCE, J. B.、ARIYAN, Z. S.、OVENDEN, G. S.
DOI:——
日期:——
Ni(0)–Cu(<scp>i</scp>): a powerful combo catalyst for simultaneous coupling and cleavage of the C–N bond with cyclization to valuable amide-based pyrroles and 4-pyridones
作者:Dipanwita Roy、Satinath Sarkar、Radha M. Laha、Nabyendu Pramanik、Dilip K. Maiti
DOI:10.1039/c5ra12115a
日期:——
We demonstrate unprecedented Ni(0)–Cu(i) combo catalysis for sequential bond activated domino N–C/C–C coupled annulation with N–C bond cleavage to afford valuable amide-based polysubstituted pyrroles and 4-pyridones selectively from β-ketoanilides.