Palladium-catalyzed and KO Bu-promoted Caryl–Oalcoholic coupling: an efficient one-pot synthesis of oxygen containing fused rings
摘要:
An efficient one-pot synthetic method has been developed for the synthesis of oxygen containing fused rings from 2'-bromo-biaryl-2-carbaldehyde via tandem reduction followed by palladium-catalyzed and (KOBu)-Bu-t-promoted C-aryl-O-alcoholic coupling. (c) 2013 Elsevier Ltd. All rights reserved.
KO<sup>t</sup>Bu mediated efficient approach for the synthesis of fused heterocycles via intramolecular O-/N-arylations
作者:Raju Singha、Atiur Ahmed、Yasin Nuree、Munmun Ghosh、Jayanta K. Ray
DOI:10.1039/c5ra07532g
日期:——
KOtBu mediated an efficient methodology has been developed for the synthesis of 6H-benzo[c]chromenes, 6H-benzo[c]chromen-6-ones, carbazoles, dibenzofurans and dibenzooxepins.
Organic Photoredox Catalysis for Pschorr Reaction: A Metal-Free and Mild Approach to 6H-Benzo[c]chromenes
作者:Gaofeng Feng、Jing-Yao He、Qi-Fan Bai、Chengan Jin
DOI:10.1055/s-0037-1610279
日期:2018.10
under mild conditions by using eosinY as a photoredox catalyst and acetonitrile as the solvent. The diazonium salts can be either preformed or generated in situ from the corresponding amines with t -BuONO. The process is amenable to gram-sale synthesis of 6 H -benzo[ c ]chromenes, which can be further transformed into both 6 H -benzo[ c ]chromen-6-ones through oxidation or to 6 H -benzo[ c ]chromen-6-amine
已开发出一种方便的有机光氧化还原 Pschorr 反应,为 6 H-苯并 [c] 色烯开辟了一条合成路线。该过程可以在温和的条件下通过使用曙红Y作为光氧化还原催化剂和乙腈作为溶剂进行。重氮盐可以由相应的胺与 t-BuONO 预先形成或原位生成。该工艺适用于6 H-苯并[ c ]色烯的克销售合成,其可以通过氧化进一步转化为6 H-苯并[ c ]色烯-6-酮或6 H-苯并[ c ]色烯-6-胺通过 sp 3 C-H 键胺化。该协议为合成 6 H-苯并 [c] 铬库提供了一条有吸引力的途径。
Visible light mediated synthesis of 6<i>H</i>-benzo[<i>c</i>]chromenes: transition-metal-free intramolecular direct C–H arylation
作者:Micaela D. Heredia、Marcelo Puiatti、Roberto A. Rossi、María E. Budén
DOI:10.1039/d1ob01673c
日期:——
A synthetic approach towards the 6H-benzo[c]chromene ring under visible light and transition-metal-free conditions has been developed. Benzochromenes are synthesized from the corresponding (2-halobenzyl) phenyl ethers or (2-halophenyl) benzyl ethers using KOtBu in dimethyl sulfoxide (DMSO) at room temperature (rt) and blue light-emitting diodes (LEDs) as the light source. This methodology replaces
已经开发了一种在可见光和无过渡金属条件下合成 6 H-苯并[ c ]色烯环的方法。苯并色烯是由相应的 (2-卤代苄基) 苯基醚或 (2-卤代苯基) 苄基醚在室温 (rt) 下使用二甲基亚砜 (DMSO) 中的 KO t Bu 和蓝色发光二极管 (LED) 作为光源合成的. 这种方法取代了配体或添加剂、高温和有毒溶剂的使用。光刺激反应对不同的官能团和 5 H-二苯并[ c , f]色烯也被有效地获得。发现了由二甲基阴离子和(2-卤代苄基)苯基醚形成的电子供体-受体复合物,它诱导 ET 作为光环化反应的第一步。此外,为了解释该反应的区域化学结果,使用 DFT 方法进行了理论分析。