Alkaloids of Lunasia amara Blanco. 4-Methoxy-2-phenylquinoline

Design, Synthesis, and Photophysical Properties of Pyrroloquinoline‐Based Compounds Showing Strong Blue Fluorescence as Potential Dyes for Biomedical Applications

“…Compound 13 was obtained by the two‐step synthetic protocol shown in Scheme (steps c and d). Chlorination of 11 with phosphoryl chloride yielded the 9‐chloro derivative 14 , which was methoxylated by reaction with sodium methoxide …”

“…Chlorination of 11 with phosphoryl chloride yielded the 9-chloro derivative 14,w hich was methoxylated by reaction with sodium methoxide. [15] The exact structures of compounds 12 and 13 were determined by 1 HNMR analysis( Figure S1-S8, SI). The spectrum of compound 12 showed ad oublet at d = 6.08 ppm andasinglet at 3.89 ppm, corresponding to the 8-Ha nd methyl group of the 6N-methylquinolinone structure, respectively.The spectrum of compound 13 showedt he 8-H doublet and 9-methoxy singlet at d = 7.08 and 4.22 ppm, respectively,o f9 -methoxy-PQ.…”

Alkylation of 2-Phenyl-4-quinolones: Synthetic and Structural Studies.

“…This observation is in accordance with the reported results regarding the alkylation of 5-unsubstituted-2-phenyl-4-quinolones. 8,9) When 4 was treated under the same conditions as 3, compounds 6 and 7 were produced (Chart 3). In this case, the amino group was deprotonated to give the intermediate 4.…”

“…8,9) The first method is less convenient, especially if a large series of N-alkylquinolones is needed. Regarding the second method, it has been reported that alkylation of 2-phenyl-4-quinolones leads predominantly to 4-alkoxyquinolines.…”

“…Among N-alkyl-quinolones studied, only N-methyl-2-phenyl-4-quinolone was obtained. 8,9) This has prompted us to reinvestigate the N-alkylation of 2-phenyl-4-quinolones and we have found that the presence of a 5-hydroxyl group is essential for the N-alkylation.…”