99329-30-3Relevant academic research and scientific papers
Pd-PEPPSI: Water-Assisted Suzuki?Miyaura Cross-Coupling of Aryl Esters at Room Temperature using a Practical Palladium-NHC (NHC=N-Heterocyclic Carbene) Precatalyst
Li, Guangchen,Shi, Shicheng,Lei, Peng,Szostak, Michal
, p. 1538 - 1543 (2018)
A Pd-PEPPSI-catalyzed (Pd=Palladium, PEPPSI=pyridine-enhanced precatalyst preparation stabilization and initiation) Suzuki-Miyaura cross-coupling of aryl esters via selective C?O cleavage at room temperature is reported. The developed catalyst system displays broad substrate scope with respect to both components under practical ambient reaction conditions using readily-available, cheap, modular, air- and moisture-stable Pd-NHC precatalyst (NHC=N-heterocyclic carbene). The use of water proved crucial for achieving high reactivity in this coupling. The catalyst system represents the mildest conditions for the Suzuki?Miyaura cross-coupling of aryl esters reported to date. The protocol also allowed for achieving TON >1,000 (TON=turnover number) in the Suzuki?Miyaura ester coupling for the first time. (Figure presented.).
METHOD FOR SYNTHESIZING SODIUM 2,2,6,6-TETRAMETHYLPIPERIDIDES
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Paragraph 0131; 0150, (2019/12/10)
There is a demand for the development of a technique according to which sodium 2,2,6,6-tetramethylpiperidides (Na-TMPs) can be economically and efficiently synthesized through simple operations including a small number of steps under mild conditions in a short period of time. Also, there is a demand for the development of a technique according to which high-quality Na-TMPs that do not contain lithium or lithium compounds such as Li-TMP can be synthesized. The method for synthesizing sodium 2,2,6,6-tetramethylpiperidides includes a step of obtaining sodium 2,2,6,6-tetramethylpiperidides by reacting, in a reaction solvent, 2,2,6,6-tetramethylpiperidines with a dispersion product obtained by dispersing sodium in a dispersion solvent or an organosodium compound having an aromatic ring obtained through a reaction with a dispersion product obtained by dispersing sodium in a dispersion solvent.
General Method for the Suzuki-Miyaura Cross-Coupling of Primary Amide-Derived Electrophiles Enabled by [Pd(NHC)(cin)Cl] at Room Temperature
Lei, Peng,Meng, Guangrong,Ling, Yun,An, Jie,Nolan, Steven P.,Szostak, Michal
, p. 6510 - 6513 (2017/12/26)
A general, highly selective method for the room temperature Suzuki-Miyaura cross-coupling of commonly encountered primary benzamides is reported. A combination of site-selective N,N-di-Boc-activation (tert-butoxycarbonyl activation) of the amide nitrogen with practical air- and moisture-stable, well-defined, and highly reactive [Pd(NHC)(cin)Cl] (NHC = N-heterocyclic carbene; cin = cinnamyl) provides a highly effective route to biaryl ketones from primary amides in high yields. For the first time, a TON of >1000 has been achieved in amide acyl cross-coupling.
ORGANIC ELECTROLUMINESCENT COMPOUND AND ORGANIC ELECTROLUMINESCENT DEVICE COMPRISING THE SAME
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Paragraph 161, (2016/06/28)
The present invention relates to a novel organic electroluminescent compound and an organic electroluminescent device comprising the same. By using the organic electroluminescent compound of the present invention, an organic electroluminescent device havi
One-pot synthesis of heteroaryl and diheteroaryl ketones through palladium-catalyzed 1,2-addition and oxidation
Kuriyama, Masami,Hamaguchi, Norihisa,Sakata, Keisuke,Onomura, Osamu
, p. 3378 - 3385 (2013/06/27)
A synthetic method was developed for the preparation of heteroaryl and diheteroaryl ketones from aldehydes and organoboronic acids through a palladium-catalyzed 1,2-addition and oxidation that uses an aryl iodide as the oxidant. This one-pot process shows high tolerance for a broad range of heterocyclic substrates by using 1.0-3.0 mol-% of the catalyst that is formed from allylpalladium chloride dimer and a thioether-imidazolinium chloride. In addition to fine-tuning the catalytic system, the use of a sterically hindered aryl iodide that has a substituent at the ortho position, such as 2-iodotoluene, is important to obtain the desired ketones with heterocyclic moieties in good to excellent yields. The one-pot synthesis of heteroaryl and diheteroaryl ketones was achieved by a palladium-catalyzed 1,2-addition and oxidation. This catalytic process with 1.0-3.0 mol-% catalyst loading tolerates a broad range of heterocyclic substrates to give ketones with heterocyclic moieties in good to excellent yields. Copyright
A rapid, solvent-free, ligandless and mild method for preparing aromatic ketones from acyl chlorides and arylboronic acids via a Suzuki-Miyaura type of coupling reaction
Bandgar,Patil
, p. 7627 - 7630 (2007/10/03)
Aromatic ketones were synthesized via a palladium catalyzed cross-coupling reaction of boronic acids with acyl chlorides in the presence of Na 2CO3 at room temperature under solvent-free conditions. The ligand-free and mild reaction conditions, highly rapid reaction rate and good to excellent yields are important features of this method.
Positional Reactivity of Dibenzofuran in Electrophilic Substitutions
Keumi, Takashi,Tomioka, Naoto,Hamanaka, Kozo,Kakihara, Hirohito,Fukishima, Masahiko,et al.
, p. 4671 - 4677 (2007/10/02)
Isomer distributions of dibenzofuran (DBF) in Friedel-Crafts acylations, Friedel-Crafts alkylations, and nitrations have been determined.The 2- and 3-positions of DBF represents most of the total reactivity.However, the ratio of 2- to 3-isomers greatly varied, depending on the nature of the electrophile.The positional reactivities have been found to be in the following sequence: 2- > 3- > 1- > 4-positions for Friedel-Crafts acylations, Friedel-Crafts benzylations, and nitrations with alkyl nitrate/Lewis acid or nitronium tetrafluoroborate.The ratios for acylations varied over a range from 13.1 to 2.9, while for benzylations and nitrations from 2.0 to 1.0.In contrast, for nitrations of DBF with nitric acid a different reactivity order was found: 3- > 2- > 1- > 4-, with the ratio varying from 0.8 to 0.03 depending on the nature of solvents used.The selectivity for the 3-substitution increased with increase in nitronium ion-like character of nitrating reagents.In particular, nitration with nitric acid in dichloromethane gave mostly 3-nitro-DBF (95percent of the four possible isomeric mixture).The charge-transfer nitration with tetranitromethane under the UV irradiation has shown a similar isomer distribution to that in nitration with nitric acid.The MNDO calculations predicts that the late transition-state model (by ?-complex) favors reactions at the 2-position while the early transition-state model (by HOMO electron density) leads to the 3-substitution.
2-(Trifluoromethylsulfonyloxy)pyridine as a Reagent for the Ketone Synthesis from Carboxylic Acids and Aromatic Hydrocarbons
Keumi, Takashi,Yoshimura, Kiichiro,Shimada, Masakazu,Kitajima, Hidehiko
, p. 455 - 460 (2007/10/02)
A new reagent 2-(trifluoromethylsulfonyloxy)pyridine (TFOP) was prepared by the reaction of sodium salt of 2-pyridinol with trifluoromethylsulfonyl chloride in dioxane.The conpound TFOP in trifluoroacetic acid has been found to intermolecularly dehydrate from benzoic acid and aromatic hydrocarbons to give the corresponding benzophenones in high yield.It was further elucidated, in the reaction of fluorene, that a variety of carboxylic acids can be used as the acyl precursor for the aromatic ketone synthesis in conjunction with the TFOP/TFA system.This acylation procedure has been applied to the synthesis of 2-acylthiophenes, which are hard to prepare in a satisfactory yield by the classical Friedel-Crafts reaction using aluminum chloride as the catalyst.
Solvent Effects on Isomer Distributions and Relative Rates in Friedel-Crafts Benzylation and Benzoylation of Dibenzofuran Derivatives
Keumi, Takashi,Nakamura, Masatoshi,Kitamura, Masao,Tomioka, Naoto,Kitajima, Hidehiko
, p. 909 - 914 (2007/10/02)
The positional reactivity order in Friedel-Crafts benzoylation and benzylation of dibenzofuran (DBF) is found to be 2 > 3 > 1 >= 4.Both the partial rate factors and the positional selectivity for the benzylation of DBF are very low compared with those of
