The chemoselective transformation of diarylethanones via either aerobicoxidative cleavage to give arylmethanoic acids or tandem aerobicoxidation/benzilic acid rearrangement/decarboxylation to give diarylmethanones has been developed. The transformation is controllable and applicable to a broad spectrum of substrates and affords the desired products in good to excellent yields. Mechanistic insights
已经开发了通过有氧氧化裂解产生芳基甲二酸或串联好氧氧化/苯甲酸重排/脱羧以产生二芳基甲酮的二芳基酮的化学选择性转化。该转化是可控的,并且适用于广泛范围的底物,并以良好至优异的产率提供所需的产物。具有控制反应的机械洞察力,11 H NMR追踪和单晶X射线衍射揭示了一个复杂的机理网络,其中提出并验证了两个常见的中间体,α-酮氢过氧化物和二芳基乙二酮,以及三个可能的途径。这些途径是相互联系的,可以通过改变反应条件来合理地切换。这种方法能够实现可扩展的合成并获得许多有价值的化合物,包括维生素B 3,苯二酸和非甾体抗炎药酮洛芬。本协议代表了在利用复杂的机械网络来控制反应路径,从同一类起始原料获得不同合成方法方面迈出的一步。
Diaryliodonium salts—XII
作者:F. Marshall Beringer、P.S. Forgione、M.D. Yudis
DOI:10.1016/s0040-4020(01)93330-7
日期:1960.1
Diphenyliodonium salts in t-butyl alchol have converted the anions of dimedone, dibenzoylmethane and tribenzoylmethane to C-phenyl, C, C-diphenyl, O-phenyl and O, C-diphenyl derivatives, the structures of which have been proved by degradation and synthesis. Reactions of dimedone in methanol or ethanol gave mainly products arising from dehydrogenation of the solvent.
α-Arylation of β-diketones has been carried out over CuO/aluminosilicate catalyst under ligand-free condition. The reaction conditions were optimized with different solvents, bases, catalyst amounts, and temperatures using acetylacetone and 4-bromobenzaldehyde as a model system. The scope of the catalytic system was extended to include various substituted aryl halides. 27 examples were successfully
Interaction of benzoin and hydrazine hydrochloride
作者:A. M. Comrie
DOI:10.1039/j39680000446
日期:——
Benzoin reacts with hydrazine hydrochloride to give among other products 3,4,5-triphenylpyrazole (1) and not 1,3,4,6-tetraphenyl-Δ2-trimidine (2), as previously reported.
Reactions of copper(II) β-diketonates under free radical conditions. II. Diazonium salts as aryl radicals source in the arylation of β-diketones
作者:Maria E. Lorris、Rudolph A. Abramovitch、Jorge Marquet、Marcial Moreno-Mañas
DOI:10.1016/s0040-4020(01)89881-1
日期:1992.1
Copper complexes of 2,2,6,6-tetramethylheptane-3,5-dione and other β-diketones afford α-aryl-β-diketones when treated with arenediazonium tetrafluoroborates and copper powder in dichloromethane