Monday, October 14, 2024
Douglass F. Taber
University of Delaware
Substituted Benzenes: The Tsukano Synthesis of Lancilactone C
Aiwen Lei of Nanchang University assembled the aniline 3 by directly coupling the amine 2 with nitrobenzene 1 (Nature Commun. 2024, 15, 4186. DOI: 10.1038/s41467-024-48540-6). Tatiana Besset of Université Rouen Normandie oxidized the benzamide 4 directly to the anisic acid derivative 5 (Chem. Commun. 2024, 60, 2244. DOI: 10.1039/D3CC05919G).
Dawei Ma of ShanghaiTech University converted the bromobenzene 6 to the nitrobenzene 7 (J. Org. Chem. 2024, 89, 6626. DOI: 10.1021/acs.joc.4c00463). Diane N. Le and Yining Ji of Merck optimized the nucleophilic anionic coupling of the phenol 9 with the fluorobenzene 8, leading to the ether 10 (Org. Lett. 2024, 26, 804. DOI: 10.1021/acs.orglett.3c03881).
Gang Zou of the East China University of Science and Technology prepared the alkyne 13 by Sonogashira coupling of the alkyne 12 with the N-sulfonyl triazene 11 (Org. Lett. 2024, 26, 4576. DOI: 10.1021/acs.orglett.4c01565). Tobias Ritter of the Max-Planck-Institut für Kohlenforschung devised a less hazardous route to diazonium salts and their derivatives (Science 2024, 384, 446. DOI: 10.1126/science.adn7006). Chengming Wang of Jinan University recently published a detailed review of aryl triazene chemistry (Org. Biomol. Chem. 2023, 21, 2059. DOI: 10.1039/D2OB02267B). Estíbaliz Merino of the Universidad de Alcalá and Cristina Nevado of the University of Zurich prepared the amide in high ee by radical addition of the α-bromoester 15 to the sulfinamide 14, followed by H-atom abstraction and rearrangement (Angew. Chem. Int. Ed. 2024, 63, e202319158. DOI: 10.1002/anie.202319158).
D. G. S. Sudhakar of GVK Biosciences prepared the benzaldehyde 18 by metalation of the benzamide 17 followed by reaction with DMF (Synthetic Commun. 2024, 54, 992. DOI: 10.1080/00397911.2024.2358355). Jinhui Hu and Yubing Huang of Wuyi University used electrolysis to couple the bromide 20 with ethyl benzoate 19, leading to the 4-alkyl ester 21 (Chem. Eur. J. 2024, 30, e202400010. DOI: 10.1002/chem.202400010). Xiaohua Xu and Zhong Jin of Nankai University devised a benzamide 22 that directed oxidative Heck coupling with ethyl acrylate 23 to give the meta-substituted product 24 (Org. Lett. 2024, 26, 4733. DOI: 10.1021/acs.orglett.4c01460). Professor Ritter combined ethyl benzene 25 with the sulfoxide 26 to give a thiathrenium salt analogue, that directed oxidative Heck coupling with ethyl acrylate to the ortho position, then could be displaced by trimethylsilyl acetylene 27, leading to the trisubstituted benzene 28 (Synlett 2024, 35, 1028. DOI: 10.1055/s-0043-1763625).
Xin Mu and Bin Yang of Xi'an Jiaotong University constructed the phenol 31 by adding the Grignard reagent 30 to the allene 29 (Org. Lett. 2024, 26, 3361. DOI: 10.1021/acs.orglett.4c00759). Chenggui Wu of the Anhui University of Chinese Medicine effected the oxidative cyclization of the pyridone 32 to the benzoate 33 (J. Org. Chem. 2024, 89, 7058. DOI: 10.1021/acs.joc.4c00449).
Lancilactone C (36), isolated from the South China evergreen liana Kadsura lancilimba, inhibited HIV replication in H9 lymphocytes at 1.4 µg/mL, showing no toxicity up to 100 µg/mL. Chihiro Tsukano of Kyoto University assembled the aromatic ring of 35 by intramolecular Diels-Alder cyclization of the diene propiolate 34, followed by oxidation to 35 (J. Am. Chem. Soc. 2023, 145, 14587. DOI: 10.1021/jacs.3c04124).
D. F. Taber, Org. Chem. Highlights 2024, October 14.
URL: https://www.organic-chemistry.org/Highlights/2024/14October.shtm