各种芳族溴化物先用n- BuLi处理,然后再用甲酸乙酯处理,然后在K 2 CO 3存在下与乙醇和分子碘反应,以高收率提供相应的芳族乙基酯。此外,通过用n- BuLi和随后用DMF处理,然后与甲醇,分子碘和K 2 CO 3反应,可以将芳族溴化物以良好的产率转化成相应的芳族甲基酯。通过用n处理,一些芳族化合物也可以高收率转化为相应的芳族酯。-BuLi,然后与甲酸乙酯或DMF进行反应,然后与分子碘和K 2 CO 3反应。本反应为无过渡金属,无一氧化碳的因此为芳族溴化物和芳族化合物到芳族酯的环境友好的一锅转化提供了新颖的途径。
An effective method for alkoxycarbonylation of (hetero)aryl bromides is developed in the presence of in situ-generated phosphinite ligands tBu2POR (R = nBu, nPr, Et or Me). For this purpose commercially available tBu2PCl was used as the pre-ligand in the presence of different alcohols. For the first time cross coupling reactions with two alcohols – one generating the ligand, the other used as substrate
在原位生成的次膦酸酯配体t Bu 2 POR(R = n Bu,n Pr,Et或Me)存在下,开发了一种用于(杂)芳基溴的烷氧羰基化的有效方法。为此目的,在不同醇存在下,将可商购的t Bu 2 PC1用作预配体。首次开发了与两种醇的交叉偶联反应-一种生成配体,另一种用作底物。通过这种方法,可以以更有效的方式进行配体优化,并且可以以良好的产率和选择性获得所需的产物。
Palladium-catalysed oxidative cross-esterification between two alcohols
作者:Jianhui Xia、Ailong Shao、Shan Tang、Xinlong Gao、Meng Gao、Aiwen Lei
DOI:10.1039/c5ob00677e
日期:——
Oxidative cross-esterification between two alcohols was achieved by using PdCl2(PPh3)2 as the sole catalyst and benzyl chloride as the oxidant.
[EN] SUBSTITUTED PYRAZOLOAZEPIN-4-ONES AND THEIR USE AS PHOSPHODIESTERASE INHIBITORS<br/>[FR] PYRAZOLOAZÉPIN-4-ONES SUBSTITUÉES ET LEUR UTILISATION EN TANT QU'INHIBITEURS DE PHOSPHODIESTÉRASE
申请人:LEO PHARMA AS
公开号:WO2018108230A1
公开(公告)日:2018-06-21
The present invention relates to novel substituted pyrazoloazepin-4-ones with phosphodiesterase inhibitory activity, as well as to their use as therapeutic agents in the treatment of inflammatory diseases and conditions.
Amide transformations involving C-N bond cleavage are recognized as difficult reactions owing to the inert nature of amides resulting from resonance. Accordingly, a strong inductive effect and geometrical distortion reasonably decrease the resonance stabilization to attenuate the C-N linkage. Although the conversion of such activated amides has been studied intensively, reaction systems for unactivated
由于由共振引起的酰胺的惰性性质,涉及 CN 键断裂的酰胺转化被认为是困难的反应。因此,强感应效应和几何失真合理地降低了共振稳定性以衰减 CN 链接。尽管已经对此类活化酰胺的转化进行了深入研究,但未活化酰胺的反应体系尚未开发。我们在此报告了三氟甲磺酸锌 (II) [Zn(OTf)(2)] 催化剂在分子内酰基重排的帮助下实现了多种未活化的叔酰胺的酯化。该反应用于在温和的反应条件下一锅脱除各种酰胺基导向基团,以高产率得到相应的酯。
Metal-Free Oxidative Esterification of Ketones and Potassium Xanthates: Selective Synthesis of α-Ketoesters and Esters
作者:Xianglin Luo、Runfa He、Qiang Liu、Yanping Gao、Jingqing Li、Xiuwen Chen、Zhongzhi Zhu、Yubing Huang、Yibiao Li
DOI:10.1021/acs.joc.9b03272
日期:2020.4.17
A novel and efficient oxidative esterification for the selectivesynthesis of α-ketoesters and esters has been developed under metal-free conditions. In the protocol, various α-ketoesters and esters are available in high yields from commercially available ketones and potassium xanthates. Mechanistic studies have proven that potassium xanthate not only promotes oxidative esterification but also provides