26031-47-0Relevant articles and documents
1,2-Dicarbofunctionalization of Trifluoromethyl Alkenes with Pyridinium Salts via a Cycloaddition/Visible-Light-Enabled Fragmentation Cascade
Chen, Guo-Shu,Chen, Shu-Jie,Deng, Tao,He, Zhi-Qing,Li, Jia-Hui,Liu, Li-Shan,Liu, Yun-Lin,Ren, Hai
supporting information, p. 702 - 707 (2022/01/28)
Although trifluoromethyl alkenes have great synthetic potential, their 1,2-difunctionalization has been a challenge. In this Letter, we disclose the first 1,2-dicarbofunctionalization of trifluoromethyl alkenes with pyridinium salts via a cascade process
Facile one-pot tandem synthesis of perfluoroalkylated indolizines under metal-free mild conditions
He, Dong,Xu, Yuhong,Han, Jing,Deng, Hongmei,Shao, Min,Chen, Jie,Zhang, Hui,Cao, Weiguo
, p. 938 - 944 (2017/01/25)
A direct metal-free method for the synthesis of perfluoroalkylated indolizines by means of DIPEA-promoted tandem C[sbnd]N/C[sbnd]C bond formation was developed. Various substituted pyridines and bromoacetyl derivatives with methyl perfluoroalk-2-ynoates proceeded smoothly in this mild transformation, and the desired products were obtained in good to excellent yields under air.
Synthesis and Nitration of Some Thieno-fused Analogues of the Benzo[a]quinolizinium Cation
Sato, Kiyoshi,Arai, Sadao,Yamagishi, Takamichi
, p. 57 - 64 (2007/10/03)
Three thieno-fused analogues of benzo[a]quinolizinium (1), thieno[3,2-a]- and thieno[2,3-a]quinolizinimn 4 and 5 and thiazolo[2,3-a]isoquinolinium (6), were synthesized by photocyclization of 1-(2-thienylvinyl)pyridinium salts 9a and 9b and 3-styrylthiazolium salt 9c, respectively. The nitration of the compounds 4, 5, and 6 occurred predominantly at positions 2, 3, and 7, respectively, while the nitro group was introduced into the 8- and 10-positions of 1 in the ratio of 68:32. The nmr and uv spectral properties and reduction potentials of 4-6 were also compared with those of the parent compound 1.
Pyridinium Ylides in Syntheses of Naphthopyrandiones and in Regioselective Syntheses of Acylated Anthraquinones Related to Fungal and Bacterial Metabolites
Aldersley, Michael F.,Chishti, Shuhid H.,Dean, Francis M.,Douglas, Mark E.,Ennis, David S.
, p. 2163 - 2174 (2007/10/02)
Improvements have been made in the use of acylated pyridinium ylides for the transformation of 2-methyl-1,4-naphthoquinone into derivatives (15) and (16) of naphthopyran-5,10-dione, containing furan and thiophene groups.The substitution and cyclisation steps can be combined effectively by using 2-phenoxymethyl- instead of 2-methyl-naphthoquinone.The use of better leaving groups than phenoxy (especially 4-nitrophenoxy) allows the quinone to react with two proportions of ylide and leads regiospecifically to 1-aroyl-2-arylanthracene-9,10-diones such as (20a).If the leaving group is nuclear bromine as in 2-bromo-3-methyl-1,4-naphthoquinone, another reaction with 2 mol equiv. of ylide leads to complex red intermediates of type (31) which in contact with alumina are quantitatively converted into the regioisomeric 2-aroyl-3-arylanthracene-9,10-diones such as (22a).The structures have been determined by standard methods but special features of the NMR spectra are reported including a case of extreme line broadening by traces of iron.Mechanisms are suggested for the diverse reactions between the quinones and the ylides.
