Provided herein are compounds of the formula (I):
as well as pharmaceutically acceptable salts thereof, wherein the substituents are as those disclosed in the specification. These compounds, and the pharmaceutical compositions containing them, are useful for the treatment of diseases such as, for example, COPD
carbon–heteroatom (C–P, C–O, C–S, and C–N) bonds via C–N cleavage of benzyl ammoniumsalts under transition-metal-free conditions was reported. The combination of t-BuOK and 18-crown-6 enabled a wide range of substituted benzyl ammoniumsalts to couple readily with different kinds of heteroatom nucleophiles, i.e. hydrogen phosphoryl compounds, alcohols, thiols, and amines. Good functional group tolerance was demonstrated
Alkyl arylethers are an important class of compounds in medicinal and agricultural chemistry. Catalytic C(sp3)−O cross‐coupling of alkyl electrophiles with phenols is an unexplored disconnection strategy to the synthesis of alkyl arylethers, with the potential to overcome some of the major limitations of existing methods such as C(sp2)−O cross‐coupling and SN2 reactions. Reported here is a tandem
烷基芳基醚是药物和农业化学中重要的一类化合物。烷基亲电试剂与酚类的催化C(sp 3)-O交叉偶联是烷基芳基醚合成的未探索的断开策略,具有克服现有方法(例如C(sp 2)-的某些主要局限性)的潜力O交叉偶联和S N 2反应。本文报道了串联的光氧化还原和铜催化以实现烷基N的脱羧C(sp 3)-O偶联‐羟基邻苯二甲酰亚胺(NHPI)与酚在温和的反应条件下形成的酯。该方法用于使用容易获得的烷基羧酸(包括许多天然产物和药物分子)合成各种烷基芳基醚。证明了在范围和功能组对现有方法的容忍度方面的互补性。
Homogeneous Palladium-Catalyzed Selective Reduction of 2,2′-Biphenols Using HCO2H as Hydrogen Source
作者:Wen Yang、Wanxiang Zhao、Ruoling Li、Chenchen Li
DOI:10.1055/a-1337-5153
日期:2021.5
efficient homogeneous palladium-catalyzed selective deoxygenation of 2,2′-biphenols by reduction of aryl triflates with HCO2H as the hydrogensource is reported. This protocol complements the current method based on heterogeneous Pd/C-catalyzed hydrogenation with hydrogen gas. This process provided the reduction products in good to excellent yields, which could be readily converted to various synthetically
To date, cleavage of the C−N bond in aromatic amides has been achieved in molecules with a distorted constitutional framework around the nitrogen atom. In this report, a nickel-catalyzed reduction of planar amides to the corresponding lower hydrocarbon homologue has been reported. This involves a one-pot reductive cleavage of the C−N bond followed by a tandem C−CO bond break in the presence of a hydride