27438-39-7Relevant articles and documents
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Patton,T.L.
, p. 1677 - 1678 (1961)
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Dioxazaborenines
Moehrle, Hans,Zuege, Erika
, p. 580 - 587 (1981)
The reaction of 2-naphthol with hexamethylenetetramine in the presence of boric acid in 2-ethoxyethanol gives the dioxazaborenine 2, which can be hydrolozed to the phenolic Mannich base 1.An analogous derivative 4 is produced from 1 and dihydroxyphenylborane (3), while hydroxydiphenylborane (5) yields a labile boron chelate 7, which on heating undergoes amine elimination to yield 8 and the quinone methide 11.
Acetyl Acetone Covalent Triazine Framework: An Efficient Carbon Capture and Storage Material and a Highly Stable Heterogeneous Catalyst
Jena, Himanshu Sekhar,Krishnaraj, Chidharth,Wang, Guangbo,Leus, Karen,Schmidt, Johannes,Chaoui, Nicolas,Van Der Voort, Pascal
, (2018/06/11)
We present, for the first time, Covalent Triazine Frameworks functionalized with acetyl acetonate group (acac-CTFs). They are obtained from the polymerization of 4,4'-malonyldibenzonitrile under ionothermal conditions and exhibit BET surface areas up to 1626 m2/g. The materials show excellent CO2 uptake (3.30 mmol/g at 273 K and 1 bar), H2 storage capacity (1.53 wt% at 77 K and 1 bar) and a good CO2/N2 selectivity (up to 46 at 298 K). The enhanced CO2 uptake value and good selectivity are due to the presence of dual polar sites (N and O) throughout the material. In addition, acac-CTF was used to anchor VO(acac)2 as a heterogeneous catalyst. The V@acacCTF showed outstanding reactivity and reusability for the modified Mannich-type reaction with a higher turnover number than the homogeneous catalyst. The higher reactivity and reusability of the catalyst comes from the coordination of the vanadyl ions to the acetyl acetonate groups present in the material. The strong metalation is confirmed from Fourier Transform Infrared analysis, 13C MAS NMR spectral analysis and X-ray photoelectron spectroscopy measurement. Detailed characterization of the V@acac-CTF reveals that electron donation from O^O of the acetyl acetonate group to VO(acac)2, combined with the very high surface area of acac-CTF, is responsible for the stabilization of the catalyst. Overall, this contribution highlights the necessity of stable catalytic binding sites on heterogeneous supports to fabricate greener catalysts for sustainable chemistry.
Manganese-Catalyzed Aminomethylation of Aromatic Compounds with Methanol as a Sustainable C1 Building Block
Mastalir, Matthias,Pittenauer, Ernst,Allmaier, Günter,Kirchner, Karl
supporting information, p. 8812 - 8815 (2017/07/12)
This study represents the first example of a manganese-catalyzed environmentally benign, practical three-component aminomethylation of activated aromatic compounds including naphtols, phenols, pyridines, indoles, carbazoles, and thiophenes in combination with amines and MeOH as a C1 source. These reactions proceed with high atom efficiency via a sequence of dehydrogenation and condensation steps which give rise to selective C-C and C-N bond formations, thereby releasing hydrogen and water. A well-defined hydride Mn(I) PNP pincer complex, recently developed in our laboratory, catalyzes this process in a very efficient way, and a total of 28 different aminomethylated products were synthesized and isolated yields of up to 91%. In a preliminary study, a related Fe(II) PNP pincer complex was shown to catalyze the methylation of 2-naphtol rather than its aminomethylation displaying again the divergent behavior of isoelectronic Mn(I) and Fe(II) PNP pincer systems.
Cu(II)-Catalyzed ortho-Selective Aminomethylation of Phenols
Dai, Jin-Ling,Shao, Nan-Qi,Zhang, Jin,Jia, Run-Ping,Wang, Dong-Hui
supporting information, p. 12390 - 12393 (2017/09/23)
A Cu(II)-catalyzed ortho-selective functionalization of free phenols with trifluoroborates to afford Csp2-Csp3 coupling products under mild conditions has been developed. A variety of functional groups on the phenol and the potassium aminomethyltrifluoroborate substrates were found compatible, furnishing the corresponding products in moderate to excellent yields. A single-electron transfer radical coupling mechanism involving a six-membered transition state is proposed to rationalize the high levels of ortho-selectivity in the reaction. This protocol provides straightforward access to ortho-aminomethyl-substituted phenols, unnatural amino acids and other bioactive small molecules.