75907-52-7Relevant articles and documents
Dimenthylphosphine P-Oxide as a Synthetic Platform for Bulky and Chiral Ligands with Dimenthylphosphino Donor Groups
Reinhardt, Katja,Koller, Sebastian,Klein, Philippe,Lossin, Corvin,Gatzka, Julia,Altmann, Philipp J.,P?thig, Alexander,Hintermann, Lukas
, p. 1 - 19 (2022/01/12)
Attaching di(1R)-menthylphosphino fragments (menthyl = Men = 1R,2S,5R-2-isopropyl-5-methylcyclohex-1-yl) to molecular scaffolds turns them into homochiral, bulky, electron-rich phosphine ligands with proven and potential applications in coordination chemistry and transition-metal catalysis. Dimenthylphosphine P-oxide (Men2POH; 1) is established as a platform chemical toward dimenthylphosphino-containing targets via transformation to the known ligand precursors dimenthylchlorophosphine (4) and dimenthylphosphine (6). Transformations of 1 to dimenthylphosphinyl chloride (5) and dimenthylphosphinic acid (8) are elaborated. A phospha-Michael type 1,4-addition of 1 to p-benzo-or 1,4-naphthoquinone gives the corresponding o-hydroxyaryl(dimenthyl)phosphine oxides. Deprotonation of 1 with n-BuLi provides a phosphinyl nucleophile, whose reactions with alkyl halides or 1,n-dihaloalkanes provide tertiary alkyl dimenthylphosphine oxides or 1,n-bis(dimenthylphosphino)alkane bis(P-oxides) 10a-c, respectively. As an example, oxide 10b was deoxygenated to the diphosphine Men2P(CH2)3PMen2 (11) and characterized via the square-planar complex [(Men2P(CH2)3PMen2)PdCl2] (12). A selection of P-aryl dimenthylphosphines, including PhP(Men)2 (19) and 2-ClC6H4P(Men)2 (22), as well as the menthyl analogues Men-JohnPhos (21) and Men-SPhos (24), of the respective Buchwald ligands have been prepared. The combination of the secondary phosphine oxide (SPO) 1 with PdCl2 produces halide-bridged [(Men2POH)2Pd2Cl2] (25), mononuclear [(Men2POH)2PdCl2] (26), or the halide-bridged pseudochelate complex [(Men2PO···H···OPMen2)2Pd2Cl2] (27), depending on the reaction stoichiometry and conditions, all of which have been crystallographically characterized. The new ligands 1, 19, 21, 22, and 24 and complexes 25 and 26 have been evaluated in model palladium-catalyzed C-C-and C-N-fragment coupling reactions and found to display specific reactivity profiles due to the presence of the menthyl groups. Ligand 22 in particular catalyzed an asymmetric biaryl-forming coupling to give 2-methoxy-1,1′-binaphthalene with an er of up to 93:7.
Pyridine-based hypercrosslinked polymers as support materials for palladium photocatalysts and their application in Suzuki-Miyaura coupling reactions
Zhang, Yan,Zhang, Le,Zhang, Xiaoli,Yang, Didi,Du, Cheng,Wan, Liu,Au, Chaktong,Chen, Jian,Xie, Mingjiang
, p. 15202 - 15208 (2020/09/23)
A series of hypercrosslinked polymers (P1 to P8) was synthesized from pyridine and conjugated monomers to support palladium for photocatalytic Suzuki-Miyaura coupling reactions. The results of SEM, TEM and XRD analyses reveal that the supports possess a loose porous amorphous lamellar structure, and the TGA test shows that they are thermally stable. Among the prepared photocatalysts, the one using P6 as a support performed the best, displaying excellent photocatalytic and recycling performance under the irradiation of blue light at 30 °C.
Benzyloxycalix[8]arene: A new valuable support for NHC palladium complexes in C-C Suzuki-Miyaura couplings
Abdellah, Ibrahim,Kasongo, Pauline,Labattut, Axel,Guillot, Régis,Schulz, Emmanuelle,Martini, Cyril,Huc, Vincent
supporting information, p. 13843 - 13848 (2018/10/20)
Benzyloxycalix[8]arene supported catalysts bearing N-heterocyclic carbene palladium complexes on each subunit were readily synthesized. Intermediates and catalysts were fully characterized, allowing for a fine control of their structure. X-ray diffraction analysis confirmed the formation of a calix[8]arene bearing eight well-defined NHC palladium complexes. The macrocyclic structure of calix[8]arenes allowed for a scalable and chromatography-free catalyst synthesis under homogeneous conditions, while the catalytic reaction proceeded under heterogeneous conditions, just by changing the nature of the solvent. Indeed, when used as a suspension in ethanol, a high TON and TOF were obtained through a large panel of functionalized brominated substrates in C-C Suzuki-Miyaura couplings, with low metal contamination after simple filtration.
