119836-85-0Relevant articles and documents
Phosphine-catalyzed Aza-MBH reactions of vinylpyridines: Efficient and rapid access to 2,3,5-triarylsubstituted 3-pyrrolines
Chen, Jing,Li, Jianjun,Wang, Jiazhe,Li, Hao,Wang, Wei,Guo, Yuewei
, p. 2214 - 2217 (2015)
Vinylpyridines have been developed in aza-Morita-Baylis-Hillman (MBH) reaction to construct triarylsubstituted 3-pyrrolines. The first electron-deficient aromatic ring is marked as an activating mode for the vinyl group in the MBH reaction. This method provides efficient and rapid access to a range of triarylpyrrolines in good yields and at an excellent level of diastereoselectivity. Moreover, the synthetic potential of this protocol is further enhanced by the straightforward synthesis of unsymmetrical tri- and polyarylsubstituted pyrroles.
Organocatalytic enantioselective direct additions of aldehydes to 4-vinylpyridines and electron-deficient vinylarenes and their synthetic applications
Wang, Sinan,Li, Xiangmin,Liu, Hongwei,Xu, Li,Zhuang, Jinchen,Li, Jian,Li, Hao,Wang, Wei
supporting information, p. 2303 - 2310 (2015/03/04)
We describe a synergistic catalysis strategy for the asymmetric direct addition of simple aldehydes to 4-vinylpyridines. By means of independent activation of weakly electrophilic 4-vinylpyridines by the Bronsted acid CF3SO3H (TfOH) and aldehydes by chiral diphenylprolinol tert-butyldimethylsilyl (TBDMS) ether-catalyzed formation of nucleophilic enamines in a cooperative manner, the previously unattainable highly enantioselective addition process has been realized for the first time. Notably, the power of the addition process is fueled by its high efficiency in the production of synthetically valued chiral pyridines. 1H NMR studies of the process suggested that the nucleophilic enamine formed in situ from the chiral amine catalyst and the aldehyde is directly added to the trimeric 4-vinylpyridinium-derived species as a highly active electrophile generated from the 4-vinylpyridine in the presence of TfOH. Moreover, inspired by the similar electronic natures of pyridine and nitrobenzene, we have achieved an unprecedented chiral diphenylprolinol TBDMS ether-promoted, highly enantioselective direct addition of aldehydes to 2-nitrostyrenes without the use of TfOH as a cocatalyst. In this approach, introducing a strong electron-withdrawing group such as NO2, CF3, SO2Me, etc. on the 2-nitrostyrene creates a highly electrophilic vinyl moiety, which enables the direct addition of the in situ-formed enamine derived from the chiral amine promoter and the aldehyde. This method significantly expands the scope of the enantioselective addition process. While the electron-withdrawing nitro group is essential for activation of the vinyl group, we have demonstrated that it can be readily transformed to diverse functionalities. Furthermore, as shown, a chiral pyridine adduct serves as a key building block in the synthesis of the potent fibrinogen receptor antagonist L-734,217.
SUBSTITUTED HETEROAROMATIC PYRAZOLE-CONTAINING CARBOXAMIDE AND UREA DERIVATIVES AS VANILLOID RECEPTOR LIGANDS
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Page/Page column 130, (2013/03/26)
The invention relates to substituted heteroaromatic pyrazole-containing carboxamide and urea derivatives as vanilloid receptor ligands, to pharmaceutical compositions containing these compounds and also to these compounds for use in the treatment and/or prophylaxis of pain and further diseases and/or disorders.
