Synthesis of bulky arylphosphanes by rhodium-catalyzed formal [2+2+2] cycloaddition reaction and their use as ligands.
Synthesis of bulky arylphosphanes by rhodium-catalyzed formal [2+2+2] cycloaddition reaction and their use as ligands.
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DOI：
10.1002/asia.200800102
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发表时间：
2008-09
期刊：
影响因子：
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通讯作者：
Takayuki Kobatake;Azusa Kondoh;S. Yoshida;H. Yorimitsu;K. Oshima
中科院分区：
文献类型：
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作者：
Takayuki Kobatake;Azusa Kondoh;S. Yoshida;H. Yorimitsu;K. Oshima
在阳离子铑催化剂存在下，1-炔基磷烷硫化物与1，6-或1，7-二炔发生[2+2+2]环加成反应，得到相应的芳族磷烷硫化物。在环加成中形成的芳环天然地在磷原子的邻位带有一个或两个取代基，这在磷原子周围产生空间位阻环境。在自由基条件下或在三（二甲氨基）膦的帮助下，产物的以下缩合反应是容易的，提供相应的大体积膦。二环己基（2，6-二苯基芳基）膦，这是通过这个序列，证明作为一个有效的配体在钯催化的交叉偶联胺化反应。
Treatment of 1-alkynylphosphane sulfides with 1,6- or 1,7-diynes in the presence of a cationic rhodium catalyst results in a formal [2+2+2] cycloaddition reaction to afford the corresponding aromatic phosphane sulfides. The aromatic rings formed in the cycloaddition naturally bear one or two substituents at the ortho positions to the phosphorus atom, which creates a sterically hindered environment around the phosphorus atom. The following desulfidation of the products is facile under radical conditions or with the aid of tris(dimethylamino)phosphane, providing the corresponding bulky phosphanes. Dicyclohexyl(2,6-diphenylaryl)phosphane, which is available through this sequence, proves to serve as an efficient ligand in palladium-catalyzed cross-coupling amination reactions.