Rhodium-Catalyzed Xanthone Formation from 2-Aryloxybenzaldehydes via Cross-Dehydrogenative Coupling (CDC)
摘要:
A concise and straightforward strategy to construct a xanthone skeleton via an intramolecular cross-dehydrogenative coupling (CDC) of 2-aryloxybenzaldehydes has been developed. The reaction proceeded smoothly without any need of preactivation of the aldehyde group. It can tolerate various functional groups and provides an applicable protocol to construct a wide range of xanthone derivatives.
The present invention relates to compounds according to formula 1,
which exhibit cytotoxic activity. The compounds may be used in the treatment of cancer.
本发明涉及符合式1的化合物,具有细胞毒活性。这些化合物可用于治疗癌症。
NHC-Organocatalyzed C<sub>Ar</sub>
−O Bond Cleavage: Mild Access to 2-Hydroxybenzophenones
rearrangement of acyl-anion equivalents generated by N-heterocyclic carbene (NHC) catalysis has been achieved. The developed method includes CAr−O, CAr−S, or CAr−N bondcleavage for the formation of a CAr−C bond and enables access to 2-hydroxybenzophenones, an important structural motif that is present in several bioactive natural products. By utilizing this procedure, the alkaloid taxilamine was synthesized
N杂环卡宾(NHC)催化产生的酰基阴离子当量的Truce-Smiles重排已实现。所开发的方法包括裂解C Ar -O,C Ar -S或C Ar -N键以形成C Ar -C键,并能够获得2-羟基二苯甲酮,这是几种生物活性天然存在的重要结构基序产品。通过使用该程序,生物碱紫杉胺分三步合成。DFT计算和控制实验支持经典S NAr机理是与催化剂结合的Meisenheimer型中间体。该方法具有温和的反应条件,出色的官能团耐受性和广泛的底物范围,包括各种类别的(杂)芳烃。
An organocatalytic method for the synthesis of some novel xanthene derivatives by the intramolecular Friedel–Crafts reaction
作者:Tülay Yıldız、Hatice Başpinar Küçük
DOI:10.1039/c6ra27094h
日期:——
An efficient organocatalytic method for the synthesis of new substituted 9-arylxanthenes (2a–2u) starting from diarylcarbinol compounds with an arenoxy group (1a–1u) has been developed using the intramolecular Friedel–Crafts reaction. The substrates were prepared in two steps by Ullmann-type coupling and then Grignard reaction. Some organic Brønsted acids were studied as catalysts (3a–3g) in the intramolecular
Rearrangement of 2-Aryloxybenzaldehydes to 2-Hydroxybenzophenones by Rhodium-Catalyzed Cleavage of Aryloxy CO Bonds
作者:Honghua Rao、Chao-Jun Li
DOI:10.1002/anie.201103599
日期:2011.9.12
Lost in the shuffle: An unprecedented rearrangement of the title compounds proceeds by the simultaneous rhodium‐catalyzed cleavage of aryloxy CO and aldehyde CH bonds (see scheme). The reaction tolerates the presence of various catalytically reactive substituents such as aryl halides, nitrile, and esters.
A HOAc‐catalyzed aryloxy/alkoxy‐assisted nucleophilic addition of 2‐methylquinolines to aldehydes in water has been described. The reaction provides an efficient and direct access to hydroxyquinolines in moderate to good yields. In addition, a HOAc/1,3‐DMBBA (1,3‐dimethylbarbituric acid) synergistic organocatalysis system were also developed for the synthesis of alkenylquinolines.