1807-97-2Relevant academic research and scientific papers
A visible-light-photocatalytic water-splitting strategy for sustainable hydrogenation/deuteration of aryl chlorides
Ling, Xiang,Xu, Yangsen,Wu, Shaoping,Liu, Mofan,Yang, Peng,Qiu, Chuntian,Zhang, Guoqiang,Zhou, Hongwei,Su, Chenliang
, p. 386 - 392 (2020/02/25)
Hydrogenation/deuteration of carbon chloride (C?Cl) bonds is of high significance but remains a remarkable challenge in synthetic chemistry, especially using safe and inexpensive hydrogen donors. In this article, a visible-light-photocatalytic watersplitting hydrogenation technology (WSHT) is proposed to in-situ generate active H-species (i.e., Had) for controllable hydrogenation of aryl chlorides instead of using flammable H2. When applying heavy water-splitting systems, we could selectively install deuterium at the C?Cl position of aryl chlorides under mild conditions for the sustainable synthesis of high-valued added deuterated chemicals. Sub-micrometer Pd nanosheets (Pd NSs) decorated crystallined polymeric carbon nitrides (CPCN) is developed as the bifunctional photocatalyst, whereas Pd NSs not only serve as a cocatalyst of CPCN to generate and stabilize H (D)-species but also play a significant role in the sequential activation and hydrogenation/deuteration of C?Cl bonds. This article highlights a photocatalytic-WSHT for controllable hydrogenation/deuteration of low-cost aryl chlorides, providing a promising way for the photosynthesis of high-valued added chemicals instead of the hydrogen evolution.
Visible-Light-Induced C2 Alkylation of Pyridine N-Oxides
Zhang, Wen-Man,Dai, Jian-Jun,Xu, Jun,Xu, Hua-Jian
supporting information, p. 2059 - 2066 (2017/02/26)
A photoredox catalytic method has been developed for the direct C2 alkylation of pyridine N-oxides. This reaction is compatible with a range of synthetically relevant functional groups for providing efficient synthesis of a variety of C2-alkylated pyridine N-oxides under mild conditions. Mechanistic studies are consistent with the generation of a radical intermediate along the reaction pathway.
On the Structure and Mechanism of Formation of the Lansbury Reagent, Lithium Tetrakis(N-dihydropyridyl)aluminate
Tanner, Dennis D.,Yang, Chi-Ming
, p. 1840 - 1846 (2007/10/02)
The reaction of lithium aluminium hydride (LAH) and pyridine yields five lithium tetrakis(N-dihydropyridyl)aluminate (LDPA) isomers.The LDPA isomers are formed reversibly and contain both 1,2- and 1,4-dihydropyridyl ligands.The 1,2-dihydropyridyl ligands are incorporated as the products of kinetic control while the 1,4-dihydropyridyl ligands are formed as the thermodynamic products.When LDPA is synthesized using lithium aluminium deuteride and the deuterated LDPA is placed in pyridine solvent, the ligands exchange with the pyridine in the solvent pool and form pyridine which is deuterated mainly in the 2- and 4-position.A small amount of 3-deuterated pyridine is also detected.The formation of 3-deuteriopyridine suggests that the pyridine radical anion is an intermediate present during the reaction of LAH with pyridine.In support of this suggestion, when LAH and pyridine are mixed, the EPR spectrum of the lithium salt of the pyridyl radical anion is observed.The stepwise addition of ligands to form LDPA is observed (NMR).Five aluminate species are detectable (27Al NMR): LAH , mono-, di-, and -trisubstituted aluminium hydride, and LDPA.The hydrolysis of LDPA in solvent pyridine-d5 yields a mixture of 1,4-, 1,2-, and 2,5-dihydropyridines.The dihydropyridines are stable in the absence of oxygen.
Functionalization of Pyridine via Direct Metallation
Verbeek, Jacob,George, Albert V. E.,Jong, Robertus L. P. de,Brandsma, Lambert
, p. 257 - 258 (2007/10/02)
The isolation of mixtures of 2-, 3-, and 4-deuteriopyridine, 2-, 3-, and 4-trimethylsilylpyridine, or 2-, 3-, and 4-methylthiopyridine indicates successful metallation of pyridine with a 1:1 mixture of BuLi-ButOK in tetrahydrofuran-hexane at -100 deg C.
Direct, Regiospecific 2-Lithiation of Pyridines and Pyridine 1-Oxides with in Situ Electrophilic Trapping
Taylor, Stephen L.,Lee, David Y.,Martin, J. C.
, p. 4156 - 4158 (2007/10/02)
Efficient synthetic routes to 2-substituted pyridines and 2,6-disubstituted pyridine 1-oxides involving direct lithiation with the sterically hindered base lithium 2,2,6,6-tetramethylpiperidide (LiTMP) in the presence of electrophiles that are compatible with the base, e.g., trimethylsilyl chloride (Me3SiCl) and hexafluoroacetone (HFA), are described.
PREPARATION AND MICROWAVE SPECTRA OF PYRIDINE N-OXIDE AND DEUTERATED PYRIDINE N-OXIDES, COMPLETE MOLECULAR STRUCTURE OF PYRIDINE N-OXIDE.
Sorensen, G. O.,Tang-Pedersen, A.,Pedersen, E. J.
, p. 263 - 268 (2007/10/02)
Pyridine N-oxide and the monodeuterated species have been prepared and their microwave spectra investigated for J-values up to 10.The complete rs structure is determined from these data combined with data from earlier measurements on the 13C- and the 15N-substituted species .The N-O bond length obtained here is intermediate between the typical single and double bond length found in other gas phase molecular structures.The structure of the C-N-C part of pyridine N-oxide is found to be significantly different from the corresponding part of the pyridine structure.
Hydrogen-deuterium exchange of heteroaromatics in neutral D2O at elevated temperatures
Werstiuk, Nick Henry,Timmins, George
, p. 1022 - 1024 (2007/10/02)
Pyridine (1), 2-methylpyridine (2), 3-methylpyridine (3), 4-methylpyridine (4), and 1,10.phenanthroline undergo H-D exchange in neutral D2O at elevated temperatures (180-300 deg C).With a suitable choice of temperature and reaction time it is possible to prepare selectively deuterated or perdeuterated substrates in good yield.
