在无光催化剂的情况下,用可见光照射9酯取代的蒽会导致形成内过氧化物,然后进一步进行碱辅助裂解,从而制得蒽醌。能量转移产生的蒽的激发态物质,与3 O 2相互作用,通过能量转移提供1 O 2,并与1 O 2进行环加成反应。通过使用钯(II)催化和可见光介导的转化,我们开发了一种有效的合成方案,可从容易获得的二芳基羧酸中获得各种蒽醌。在30°C的O 2下,用30 W荧光灯照射,在叔戊醇中用乙酸钯(II),Ac-Ile-OH,苯醌和碳酸钾获得最佳结果。
Coupling of Reformatsky Reagents with Aryl Chlorides Enabled by Ylide‐Functionalized Phosphine Ligands
作者:Zhiyong Hu、Xiao‐Jing Wei、Jens Handelmann、Ann‐Katrin Seitz、Ilja Rodstein、Viktoria H. Gessner、Lukas J. Gooßen
DOI:10.1002/anie.202016048
日期:2021.3.15
organozinc reagents with aryl electrophiles using a cyclohexyl‐YPhos ligand bearing an ortho‐tolyl‐substituent in the backbone. This highly electron‐rich, bulky ligand enables the use of arylchlorides in room temperature couplings of Reformatsky reagents. The reaction scope covers diversely functionalized arylacetic and arylpropionic acid derivatives. Aryl bromides and chlorides can be converted selectively
Double Heck reaction of bridged o , o ′-dibromobiaryls with ethyl acrylate
作者:Mahavir Prashad、Yugang Liu、Xiao Yin Mak、Denis Har、Oljan Repič、Thomas J. Blacklock
DOI:10.1016/s0040-4039(02)02090-7
日期:2002.11
An inter- followed by an intramolecular double Heck reaction of bridged o,o′-dibromobiaryls with ethyl acrylate is described. The nature of the bridging atom/group determined the outcome of the reaction. This double Heck reaction strategy afforded a safe and convenient synthesis of 9-(ethoxycarbonylmethylene)-9H-xanthene and a novel route to 9 and/or 10-substituted anthracene derivatives.
Flexible and Practical Synthesis of Anthracenes through Gold-Catalyzed Cyclization of<i>o</i>-Alkynyldiarylmethanes
作者:Chao Shu、Cheng-Bin Chen、Wei-Xi Chen、Long-Wu Ye
DOI:10.1021/ol402713g
日期:2013.11
A concise gold-catalyzed method for the preparation of anthracenes from o-alkynyldiarylmethanes has been developed. Under mild reaction conditions, versatile anthracene derivatives were formed in moderate to good yields. The high flexibility, broad substrate scope, and mild nature of this reaction render it a viable alternative for the synthesis of anthracenes.