460743-71-9Relevant articles and documents
Tetraethylphosphorodiamidate-Directed Metalation Group: Directed Ortho and Remote Metalation, Cross Coupling, and Remote Phospha Anionic Fries Rearrangement Reactions
Alessi, Manlio,Blackburn, Thomas,Patel, Jignesh J.,Sawinski, Hannah,Snieckus, Victor
, (2020/05/18)
The linked directed ortho and remote metalation (DoM and DreM) and cross-coupling reactions of aryl phosphorodiamidates (Ar-OP(O)(NEt2)2) is reported. The o-iodo and o-boronato aryl tetraethylphosphorodiamidates 3, prepared by DoM, undergo orthogonal Ni- and Pd-catalyzed Suzuki-Miyaura cross coupling to furnish biaryls 4 and 5 in good to excellent yields. Silicon group protection of biaryl 4 via DoM followed by previously unobserved DreM phospha anionic Fries rearrangement affords biaryls 11 which, under acidic conditions, furnish oxaphosphorine oxides 12.
Bis(dialkylphosphino)ferrocene-Ligated Nickel(II) Precatalysts for Suzuki-Miyaura Reactions of Aryl Carbonates
Barth, Emily L.,Davis, Ryan M.,Mohadjer Beromi, Megan,Walden, Andrew G.,Balcells, David,Brudvig, Gary W.,Dardir, Amira H.,Hazari, Nilay,Lant, Hannah M. C.,Mercado, Brandon Q.,Peczak, Ian L.
supporting information, p. 3377 - 3387 (2019/09/30)
Aryl carbonates, a common protecting group in synthetic organic chemistry, are potentially valuable electrophiles in cross-coupling reactions. Here, after performing a thorough evaluation of different precatalysts, we demonstrate that (dcypf)Ni(2-ethylphenyl)(Br) (dcypf = 1,1-bis(dicyclohexylphosphino)ferrocene) is an efficient precatalyst for Suzuki-Miyaura reactions using a variety of aryl carbonates as substrates. Mechanistic studies indicate that (dcypf)Ni(2-ethylphenyl)(Br), which contains a bidentate phosphine that binds in a trans geometry, is an effective precatalyst for these reactions for two reasons: (i) it rapidly forms the Ni(0) active species and (ii) it minimizes comproportionation reactions between the Ni(0) active species and both the unactivated Ni(II) precatalyst and on-cycle Ni(II) complexes to form catalytically inactive Ni(I) species. In contrast, the state of the art precatalyst (dppf)Ni(o-tolyl)(Cl) (dppf = 1,1-bis(diphenylphosphino)ferrocene), which contains a bidentate phosphine that binds in a cis geometry, forms Ni(I) species during activation and is essentially inactive for aryl carbonate couplings. Although the exact reasons on a molecular level why the dcypf system is more active than the dppf system are unclear, our results indicate that in general Ni catalysts supported by the dcypf ligand will give better performance for catalytic reactions involving substrates which undergo relatively slow oxidative addition, such as aryl carbonates.
Revisitation of Organoaluminum Reagents Affords a Versatile Protocol for C-X (X = N, O, F) Bond-Cleavage Cross-Coupling: A Systematic Study
Ogawa, Hiroyuki,Yang, Ze-Kun,Minami, Hiroki,Kojima, Kumiko,Saito, Tatsuo,Wang, Chao,Uchiyama, Masanobu
, p. 3988 - 3994 (2017/06/19)
A revisit of organoaluminum reagents for cross-coupling reactions has opened up several types of C-C bond formation protocols through cleavage of phenolic/alcoholic C-O and C-F and ammonium C-N bonds. Catalyzed by the commercially available NiCl2(PCy3)2 catalyst, these reactions proceed smoothly with a wide range of substrates and broad functional group compatibility, providing a versatile methodology for organoaluminum-mediated cross-coupling processes.
