959020-16-7Relevant articles and documents
Radical chain monoalkylation of pyridines
Dénès, Fabrice,Jangra, Harish,Meléndez, Camilo,Mulliri, Kleni,Renaud, Philippe,Rieder, Samuel,Zipse, Hendrik
, p. 15362 - 15373 (2021/12/14)
The monoalkylation of N-methoxypyridinium salts with alkyl radicals generated from alkenes (via hydroboration with catecholborane), alkyl iodides (via iodine atom transfer) and xanthates is reported. The reaction proceeds under neutral conditions since no acid is needed to activate the heterocycle and no external oxidant is required. A rate constant for the addition of a primary radical to N-methoxylepidinium >107 M-1 s-1 was experimentally determined. This rate constant is more than one order of magnitude larger than the one measured for the addition of primary alkyl radicals to protonated lepidine demonstrating the remarkable reactivity of methoxypyridinium salts towards radicals. The reaction has been used for the preparation of unique pyridinylated terpenoids and was extended to a three-component carbopyridinylation of electron-rich alkenes including enol esters, enol ethers and enamides.
Organometallic compound and organic light-emitting device including the same
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Paragraph 0353; 0354; 0355; 0356; 0357; 0358, (2016/10/07)
Organic metal compound and said organometallic compounds is disclosure is an organic light emitting device. (by machine translation)
Transition-metal-free BF3-mediated oxidative and non-oxidative cross-coupling of pyridines
Chen, Quan,Leon, Thierry,Knochel, Paul
supporting information, p. 8746 - 8750 (2014/08/18)
We report a BF3-mediated direct alkynylation of pyridines at C(2) by using a variety of alkynyllithium reagents (oxidative cross-coupling). Moreover, we have developed a novel transition-metal-free cross-coupling method between alkylmagnesium reagents and 4-substituted pyridines, such as isonicotinonitrile and 4-chloropyridine, by employing BF3· OEt2 as a promoter. The combination of these methods enabled us to efficiently prepare a range of di-, tri-, and tetrasubstituted pyridines. Oxidative or non-oxidative - That is the question! Pyridines bearing a substituent at position 4 readily undergo a BF3-mediated oxidative coupling at position 2 with a wide range of alkynyllithium compounds. In contrast, 4-cyano- or 4-chloropyridines undergo a novel BF3-mediated cross-coupling at position 4 with alkylmagnesium reagents. The combination of the two transition-metal-free procedures allows the preparation of a broad range of pyridines.