An efficient and conceptually new protocol for C–Secrosscoupling of potassium selenocyanate with arylhalides via copper-catalyzed cascade reaction has been developed in water. Utilizing this protocol, a variety of aryl and heteroaryl halides were reacted with potassium selenocyanate to afford the corresponding diaryl selenides in moderate to good yields.
efficient, and eco-friendly synthetic protocol has been developed for the preparation of diaryl seleniumcompounds. To the best of our knowledge, this is the first Letter on the use of selenium dioxide as selenium source for the synthesis of diaryl selenides. Compared with other selenium sources the new source SeO2 gives an environment-friendly and low-cost synthetic route, which may be useful for
Unexpected C−Se Cross-Coupling Reaction: Copper Oxide Catalyzed Synthesis of Symmetrical Diaryl Selenides via Cascade Reaction of Selenourea with Aryl Halides/Boronic Acids
作者:V. Prakash Reddy、A. Vijay Kumar、K. Rama Rao
DOI:10.1021/jo102017g
日期:2010.12.17
Selenourea is used as an effective selenium surrogate in the C−Se cross-couplingreaction catalyzed by copper oxide nanoparticles under ligand free conditions. This protocol has been utilized for the synthesis of a variety of symmetrical diaryl selenides in good to excellent yields from the readily available arylhalides/boronicacids.
An efficient cyclization toward a cyclic tetramer of dithienothiophene (DTT) linked by divalent selenium atoms has been developed via palladium‐catalyzed coupling reaction of (nBu3Sn)2Se. X‐ray analysis revealed its highly symmetrical structure had an alternate arrangement of DTT units. There are several Se⋅⋅⋅π interactions forming a supramolecular network leading to large void channel space. The cyclic
通过(n Bu 3 Sn)2 Se的钯催化偶联反应,已经开发出了有效的环化成环二硫噻吩(DTT)的环四聚体,该环四噻吩通过二价硒原子连接。X射线分析显示其高度对称的结构具有DTT单元的替代排列。有多个Se⋅⋅⋅ππ相互作用形成超分子网络,从而导致大的空隙通道空间。环状四聚体具有中等的供电子能力。此外,环状四聚体在固态下以1:2的比例与C 60络合,形成高度对称的C 60三维阵列。
Nano Copper Oxide Catalyzed Synthesis of Symmetrical Diaryl Selenides via Cascade Reaction of KSeCN with Aryl Halides
An unprecedented transfer of selenium ion from potassium selenocyanate was observed in C-Se cross-coupling reaction catalyzed by copper oxide nanoparticles under ligand-free conditions. Utilizing this protocol wide range of symmetrical diaryl selenides were obtained in excellent yields. Nano-CuO is recyclable up to four cycles without loss of catalytic activity.