717-74-8Relevant articles and documents
Caporusso et al.
, p. 914 (1977)
Synthesis methodology, stability, acidity, and catalytic behavior of the 18 × 10 member ring pores ITQ-33 zeolite
Moliner, Manuel,Diaz-Cabanas, Maria J.,Fornes, Vicente,Martinez, Cristina,Corma, Avelino
, p. 101 - 109 (2008)
We used a flexible organic structure-directing agent (OSDA) and high-throughput (HT) synthesis techniques to explore a large composition region. A zeolite with the largest pores reported to date (ITQ-33) was found under very unusual synthesis conditions, together with other known structures. A second HT experimental design allowed, finally synthesizing pure ITQ-33. We studied the thermal and hydrothermal stability and acid properties of the zeolite. We investigated the role of pore diameter on zeolite acid strength by comparing the 18-ring pore (ITQ-33) with a 12-MR pore (ITQ-17) zeolite with the same framework composition. Finally, we compared the catalytic properties of ITQ-33 for reactant molecules of different sizes with those of 12-MR (Beta) and 14-MR (UTD-1) zeolites.
Two derivatives of phenylpyridyl-fused boroles with contrasting electronic properties: Decreasing and enhancing the electron accepting ability
He, Jiang,Rauch, Florian,Krummenacher, Ivo,Braunschweig, Holger,Finze, Maik,Marder, Todd B.
, p. 355 - 361 (2021/01/11)
Two derivatives of phenylpyridyl-fused boroles were prepared via functionalization of the pyridyl groups, namely to an electron-rich dihydropyridine moiety (compound 1) and an electron-deficient N-methylpyridinium cation (compound 2). Due to strong conjugation between the dihydropyridine moiety and the boron atom, the reduction potential of compound 1 shifts cathodically. In contrast, compound 2 exhibits three reduction processes with a first reversible reduction potential anodically shifted in comparison to its precursor (TipPBB2) or the non-borylated framework 1-methyl-2-phenylpyridin-1-ium triflate (3). The significantly anodically shifted reduction potential indicates the extreme electron deficiency of compound 2, which also leads to the reversible coordination of THF. Photophysical properties of both compounds in different solvents were investigated. Theoretical studies further support the strong conjugation in the ground state of compound 1 and the electron-deficient property of compound 2.
Hydrodehalogenation of Aryl Halides through Direct Electrolysis
Ke, Jie,Wang, Hongling,Zhou, Liejin,Mou, Chengli,Zhang, Jingjie,Pan, Lutai,Chi, Yonggui Robin
supporting information, p. 6911 - 6914 (2019/05/10)
A catalyst- and metal-free electrochemical hydrodehalogenation of aryl halides is disclosed. Our reaction by a flexible protocol is operated in an undivided cell equipped with an inexpensive graphite rod anode and cathode. Trialkylamines nBu3N/Et3N behave as effective reductants and hydrogen atom donors for this electrochemical reductive reaction. Various aryl and heteroaryl bromides worked effectively. The typically less reactive aryl chlorides and fluorides can also be smoothly converted. The utility of our method is demonstrated by detoxification of harmful pesticides and hydrodebromination of a dibrominated biphenyl (analogues of flame-retardants) in gram scale.
Dual Roles for Potassium Hydride in Haloarene Reduction: CSNAr and Single Electron Transfer Reduction via Organic Electron Donors Formed in Benzene
Barham, Joshua P.,Dalton, Samuel E.,Allison, Mark,Nocera, Giuseppe,Young, Allan,John, Matthew P.,McGuire, Thomas,Campos, Sebastien,Tuttle, Tell,Murphy, John A.
supporting information, p. 11510 - 11518 (2018/09/12)
Potassium hydride behaves uniquely and differently than sodium hydride toward aryl halides. Its reactions with a range of haloarenes, including designed 2,6-dialkylhaloarenes, were studied in THF and in benzene. In THF, evidence supports concerted nucleophilic aromatic substitution, CSNAr, and the mechanism originally proposed by Pierre et al. is now validated through DFT studies. In benzene, besides this pathway, strong evidence for single electron transfer chemistry is reported. Experimental observations and DFT studies lead us to propose organic super electron donor generation to initiate BHAS (base-promoted homolytic aromatic substitution) cycles. Organic donor formation originates from deprotonation of benzene by KH; attack on benzene by the resulting phenylpotassium generates phenylcyclohexadienylpotassium that can undergo (i) deprotonation to form an organic super electron donor or (ii) hydride loss to afford biphenyl. Until now, BHAS reactions have been triggered by reaction of a base, MOtBu (M = K, Na), with many different types of organic additive, all containing heteroatoms (N or O or S) that enhance their acidity and place them within range of MOtBu as a base. This paper shows that with the stronger base, KH, even a hydrocarbon (benzene) can be converted into an electron-donating initiator.