C<sub>6</sub>
-Selective Direct Arylation of 2-Phenylpyridine <i>via</i>
an Activated <i>N</i>
-methylpyridinium Salt: A Combined Experimental and Theoretical Study
incorporation studies revealed that the C−Hbond acidity is improved significantly in N‐methylpyridinium salts compared with their N‐Oxide and N‐iminopyridinium ylide counterparts, thus solving the long‐standing problem associated with previous strategies for the synthesis of diaryl pyridines. Finally, the control experiments and DFT calculations supported a Pd‐catalyzed and Cu‐mediated mechanism in
Synthesis of γ-Pyrones and <i>N</i>-Methyl-4-pyridones via the Au Nanoparticle-Catalyzed Cyclization of Skipped Diynones in the Presence of Water or Aqueous Methylamine
were not seen. The reaction does not proceed via the initial 1,3-transposition of the skipped diynones to their corresponding conjugated 1,3-diynone isomers. If aqueous methylamine is added, N-methyl-4-pyridones are exclusively formed in 69–79% yields via an analogous hydroamination/Au-catalyzed 6-endo cyclization pathway.
负载在 TiO 2上的 Au 纳米颗粒通过三键活化催化跳过的二炔酮在含水二恶烷中水合/6-内环化为 γ-吡喃酮。没有看到可以使用均相离子 Au(I) 催化剂通过竞争且通常占主导地位的 5-外环化途径形成的异构 3(2 H )-呋喃酮。该反应不会通过跳过的二炔酮的初始 1,3-转位为其相应的共轭 1,3-二炔酮异构体进行。如果加入甲胺水溶液,则通过类似的加氢胺化/Au 催化的 6-内环化途径仅以 69-79% 的产率形成N-甲基-4-吡啶酮。
WEBER H., ARCH. PHARM. <APBD-AJ>, 1975, 308, NO 8, 637-643
作者:WEBER H.
DOI:——
日期:——
HERBICIDAL PYRROLESULFONYLUREAS
申请人:E.I. DU PONT DE NEMOURS AND COMPANY
公开号:EP0546082A1
公开(公告)日:1993-06-16
Synthesis of substituted 4-pyridones and 4-aminopyridinium salts via a one-pot pyridine synthesis
Synthesis of substituted 4-benzyloxypyridinium salts by the addition of Grignard reagents to pyridine N-oxides provides an efficient route for obtaining substituted 4-pyridones or 4-aminopyridinium salts.