Benzotriazole-Mediated Conversions of Aromatic and Heteroaromatic Aldehydes to Functionalized Ketones
摘要:
Aromatic and heteroaromatic aldehydes reacted with benzotriazole and triethyl orthoformate in THF to give the corresponding alpha-(benzotriazol-1-yl)aryl ethyl ethers 7 in good yield. The novel acyl anion precursors 7 underwent smooth lithiation at the methine group followed by trapping with alkyl halides, aldehydes, ketones, and imines to yield the expected substituted intermediates of type 9, which were hydrolyzed under mild conditions without isolation. Benzaldehyde, methyl-, chloro-, and methoxy-substituted benzaldehydes, 1-naphthalenecarboxaldehyde, 2- and 3-furaldehydes, 2- and 3-thiophenecarboxaldehydes, and 2-pyridinecarboxaldehyde were all transformed in this manner into a variety of aryl and heteroaryl ketones with alkyl (10), alpha-hydroxyalkyl (12 and 13), alpha-aminoalkyl (14) and acyl(15) substituents.
Practical one-pot preparation of ketones from aryl and alkyl bromides with aldehydes and DIH via Grignard reagents
作者:Souya Dohi、Katsuhiko Moriyama、Hideo Togo
DOI:10.1016/j.tet.2012.05.059
日期:2012.8
groups, such as ester, nitrile, ketone, and nitro groups with i-PrMgCl·LiCl or PhMgCl instead of Mg, also provided the corresponding diaryl and alkyl arylketones in good yields. The above methods are simple and practical transition-metal-free methods for the preparation of various diaryl ketones and alkyl arylketones bearing electron-rich aromatic groups and electron-deficient aromatic groups, as well
通过衍生自芳基或烷基溴化物的格利雅试剂的反应,然后与芳族或脂族醛的反应以及随后用1,3-二碘的处理,可以有效地以高收率高效地制备各种二芳基酮,烷基芳基酮和二烷基酮。一锅法中的-5,5-二甲基乙内酰脲和K 2 CO 3。相同的处理的芳族溴化物轴承吸电子基团,如酯,腈,酮和硝基与我-PrMgCl·LiCl或PhMgCl代替Mg,也以良好的收率提供了相应的二芳基和烷基芳基酮。以上方法是用于制备各种带有富电子芳族基团和缺电子芳族基团的二芳基酮和烷基芳基酮以及二烷基酮的简单且实用的无过渡金属的方法。
New Efficient Nickel-Catalyzed Cross-Coupling Reaction between Two Csp<sup>3</sup> Centers
carbonyl group, cyano group) in an alkyl halide facilitates its cross-coupling reaction with various diorganozincs in the presence of Ni(acac)(2) (7.5-10 mol % in THF/NMP mixtures). These results were used to develop a new general cross-coupling reaction between functionalized diorganozincs and alkyliodides using m- or p-trifluoromethylstyrene as a reaction promotor and Ni(acac)(2) as a catalyst (7.5-10