1018-24-2Relevant articles and documents
Synthesis and Characterization of Pd exchanged MMT Clay for Mizoroki-Heck Reaction
Srivastava, Vivek
, p. 605 - 613 (2018)
We successfully synthesized Pd@MMT clay using a cation exchange process. We characterized all the synthesized Pd@MMT clays using sophisticated analytical techniques before testing them as a heterogeneous catalyst for the Mizoroki - Heck reaction (mono and double). The highest yield of the Mizoroki-Heck reaction product was recovered using thermally stable and highly reactive Pd@ MMT-1 clay catalyst in the functionalized ionic liquid reaction medium. We successfully isolated 2-aryl-vinyl phosphonates (mono-Mizoroki-Heck reaction product) and 2,2-diaryl-vinylphosphonates (double-Mizoroki-Heck reaction product) using aryl halides and dialkyl vinyl phosphonates in higher yields. The low catalyst loading, easy recovery of reaction product and 8 times catalyst recycling are the major highlights of this proposed protocol.
A hydrophilic heterogeneous cobalt catalyst for fluoride-free Hiyama, Suzuki, Heck and Hirao cross-coupling reactions in water
Sobhani, Sara,Hosseini Moghadam, Hadis,Skibsted, J?rgen,Sansano, José Miguel
, p. 1353 - 1365 (2020)
A hydrophilic heterogeneous cobalt catalyst of chitosan, denoted as mTEG-CS-Co-Schiff-base, has been successfully prepared. This newly synthesized catalyst was characterized by different methods such as XRD, FE-SEM, TEM, TGA, FT-IR, 13C{1H} CP/MAS NMR, XPS and ICP analyses. The catalyst displayed excellent activity for the palladium and fluoride-free Hiyama, Suzuki, Heck and Hirao reactions of various aryl iodides, bromides and chlorides (i.e., the most challenging aryl halides which are cheaper and more widely available than aryl iodides and bromides) in water. The presence of triethylene glycol tags with hydrophilic character on the Co-complex supported on chitosan provides dispersion of the catalyst particles in water, which leads to higher catalytic performance and also facile catalyst recovery by successive extraction. It was reused for at least six successive runs without any discernible decrease in its catalytic activity or any remarkable changes in catalyst structure. The use of water as a green solvent, without requiring any additive or organic solvent, as well as use of a low cost and abundant cobalt catalyst instead of expensive Pd catalysts along with the catalyst recovery and scalability, make this method favorable from environmental and economic points of view for the C-C and C(sp2)-P coupling reactions. Notably, this is the first report on the application of a cobalt catalyst in Hiyama reactions.
Dry reaction of diethyl cyanomethylphosphonate and tetraethyl methylenediphosphonate with benzaldehyde on solid bases
Hachemi, Messaoud,Puciova-Sebova, Monika,Toma, Stefan,Villemin, Didier
, p. 131 - 136 (1996)
Competitive Horner and Knoevenagel reactions of benzaldehyde with diethyl cyanomethylphosphonate and tetraethyl methylenediphosphonate successively on different solid bases (oxide, fluoride and mixtures) without the use of solvent were investigated. Tetraethyl methylenediphosphonate with benzaldehyde with similar conditions gave only the product of Horner's reaction. Basicity of the solid and nature of the cation (mono or divalent) of the base seemed important to explain the ratio of products formed in the Horner/Knoevenagel reactions.
C-P bond construction catalyzed by NiII immobilized on aminated Fe3O4@TiO2 yolk-shell NPs functionalized by (3-glycidyloxypropyl)trimethoxysilane (Fe3O4@TiO2 YS-GLYMO-UNNiII
Ghasemzadeh, Maryam Sadat,Akhlaghinia, Batool
, p. 5341 - 5356 (2019)
NiII immobilized on aminated Fe3O4@TiO2 yolk-shell NPs functionalized by (3-glycidyloxypropyl)trimethoxysilane (Fe3O4@TiO2 YS-GLYMO-UNNiII) was prepared as a stable, h
First reusable ligand-free palladium catalyzed C-P bond formation of aryl halides with trialkylphosphites in neat water
Iranpoor, Nasser,Firouzabadi, Habib,Rajabi Moghadam, Khashayar,Motavalli, Somayeh
, p. 55732 - 55737 (2014)
A reusable ligand-free palladium catalyzed phosphonation of aryl iodides, bromides and chlorides with trialkylphosphites is described for the first time in neat water. The aryl phosphonates are obtained in good to excellent yields. The reaction can be also performed with Ni(II) with longer reaction time. The role of tetrabutylammonium bromide in this reaction as reducing agent for generation of Pd(0) at room temperature is also demonstrated. Pd(0)/TBAB was easily reused for three runs without decreasing the efficiency.
Synthesis of arylphosphonates catalyzed by Pd-imino-Py-γ-Fe2O3 as a new magnetically recyclable heterogeneous catalyst in pure water without requiring any additive
Sobhani, Sara,Ramezani, Zohreh
, p. 29237 - 29244 (2016)
A palladium-Schiff base complex immobilized covalently on γ-Fe2O3 (Pd-imino-Py-γ-Fe2O3) was synthesized and characterized by different methods such as XRD (X-ray diffraction), SEM (scanning electron microscopy), TEM (transmission electron microscopy), FT-IR (Fourier transform infrared spectroscopy), TGA (thermogravimetric analysis), ICP (inductively coupled plasma), XPS (X-ray photoelectron spectroscopy), VSM (vibrating sample magnetometer) and elemental analysis. It was used as a new magnetically recyclable heterogeneous Pd catalyst for the synthesis of arylphosphinates via Csp2-P coupling reactions. A wide range of electrophilic benzenes were coupled successfully with triethylphosphite to generate the corresponding products in good to high yields in pure water without using any additive. The true heterogeneous Pd-imino-Py-γ-Fe2O3 could be reused simply with the aid of a magnetic bar for eight consecutive cycles without any drastic loss of its reactivity.
Reformatsky-type co-mediated synthesis of β-hydroxyphosphonates
Orsini, Fulvia
, p. 1425 - 1428 (1998)
Low-valent cobalt complexes were used in Reformatsky-type additions of α-halophosphonates to carbonyl compounds (ketones and aldehydes) to yield a variety of β-hydroxyphosphonates.
Preparation method of olefin phosphate compound
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Paragraph 0016; 0017; 0046; 0047; 0048; 0049; 0052-0061, (2017/08/28)
The invention discloses a preparation method of an olefin phosphate compound. The method comprises the following steps: arylethylene and phosphate according to a mol ratio 1:4-6 are used as raw materials; ferric chloride and copper salt are used as catalysts, and di-tert-butyl peroxide is used as an oxidizing agent; the raw materials and triethylamine are mixed, an organic solvent is added, and under the protection of inert gas, a reaction is carried out at 90-110 DEG C; after the reaction ends, washing is carried out, rotary evaporation is used for removing the solvent, and column chromatography is carried out in order to obtain the olefin phosphate compound. Base metal copper and iron are used as catalysts, reactant arylethylene and phosphate have low price, toxicity is low, the oxidizing agent is green and environmentally friendly, and the yield of the synthetic reaction of the olefin phosphate compound is high.
Mn(OAc)3-Promoted Oxidative Csp3-P Bond Formation through Csp2-Csp2 and P-H Bond Cleavage: Access to β-Ketophosphonates
Zhou, Pan,Hu, Biao,Li, Lingdan,Rao, Kairui,Yang, Jiao,Yu, Fuchao
, p. 13268 - 13276 (2017/12/26)
The Mn(OAc)3-promoted oxidative phosphonylation of N,N-dimethylenaminones with H-phosphonates, involving a chemo- and regioselective Csp2-Csp2 bond cleavage and Csp3-P bond formation in one step, provided successfully functionalized β-ketophosphonates under mild reaction conditions. Oxidative Csp3-H/P-H cross-coupling reactions via Csp3-C(C=O) bond cleavage and mechanistic studies are conducted preliminarily, and a possible mechanism is proposed. This novel method proceeds in good to excellent yields, shows operational simplicity, broad substrate scope, and large-scale preparation.
Mono and double Mizoroki-Heck reaction of aryl halides with dialkyl vinylphosphonates using a reusable palladium catalyst under aqueous medium
Lee, Han-Sheng,Pai, Shao-Hsuan,Liao, Wei-Ting,Yang, Xin-Jing,Tsai, Fu-Yu
, p. 34293 - 34299 (2017/07/17)
Operationally-simple and reusable Pd-catalyzed mono and double Mizoroki-Heck reactions of aryl halides and dialkyl vinylphosphonates using iPr2NH as a base in aqueous medium under air were developed. For aryl iodides, the reaction could be conducted at 80 °C under a low catalyst loading (0.1-1 mol%). When aryl bromides were applied, however, a greater amount of catalyst (5 mol%) and a longer reaction time at 120 °C were required. Simply changing dialkyl vinylphosphonates as the limiting reagent led to the formation of 2,2-diaryl vinylphosphonates in good to high yields. After reaction, the residual aqueous solution could be reused for both mono and double Mizoroki-Heck reactions, making the reactions greener and reducing wastage of precious metals and use of harmful organic solvents as the reaction medium.
