37488-95-2Relevant academic research and scientific papers
[NiCl2(dppp)]-catalyzed cross-coupling of aryl halides with dialkyl phosphite, diphenylphosphine oxide, and diphenylphosphine
Zhao, Yu-Long,Wu, Guo-Jie,Li, You,Gao, Lian-Xun,Han, Fu-She
supporting information; experimental part, p. 9622 - 9627 (2012/09/07)
We present a general approach to C-P bond formation through the cross-coupling of aryl halides with a dialkyl phosphite, diphenylphosphine oxide, and diphenylphosphane by using [NiCl2(dppp)] as catalyst (dppp=1,3-bis(diphenylphosphino)propane). This catalyst system displays a broad applicability that is capable of catalyzing the cross-coupling of aryl bromides, particularly a range of unreactive aryl chlorides, with various types of phosphorus substrates, such as a dialkyl phosphite, diphenylphosphine oxide, and diphenylphosphane. Consequently, the synthesis of valuable phosphonates, phosphine oxides, and phosphanes can be achieved with one catalyst system. Moreover, the reaction proceeds not only at a much lower temperature (100-120 °C) relative to the classic Arbuzov reaction (ca. 160-220 °C), but also without the need of external reductants and supporting ligands. In addition, owing to the relatively mild reaction conditions, a range of labile groups, such as ether, ester, ketone, and cyano groups, are tolerated. Finally, a brief mechanistic study revealed that by using [NiCl2(dppp)] as a catalyst, the NiII center could be readily reduced in situ to Ni0 by the phosphorus substrates due to the influence of the dppp ligand, thereby facilitating the oxidative addition of aryl halides to a Ni0 center. This step is the key to bringing the reaction into the catalytic cycle. Making bonds: C-P bonds were formed by the Ni-catalyzed cross-coupling of aryl halides and phosphorus substrates without the need of external reductants. Aryl bromides and less reactive aryl chlorides underwent smooth coupling with several different phosphorus substrates to afford phosphonates, phosphine oxides, and phosphines (see scheme; dppp=1,3-bis(diphenylphosphino)propane). Due to the mild reaction conditions, a range of labile groups, such as ether, ester, ketone, and cyano groups, are tolerated. Copyright
