Heteroaromatics: The Cho Synthesis of Decursivine

Marie-Isabelle Lannou and Geoffroy Sorin of the Université de Paris used Ag₂O to cyclize the alkyne 1 to the furan 2 (Chem. Commun. 2022, 58, 1374. DOI: 10.1039/D1CC06379K). Rishikesh Narayan of the Indian Institute of Technology Goa devised the enol phosphate 4 to convert the ketone 3 to the furan 5 (Tetrahedron 2022, 103, 132553. DOI: 10.1016/j.tet.2021.132553).

Zhen Wang of Lanzhou University used Lawesson's reagent (7) to convert the succinimide 6 to the pyrrole 8 (Org. Chem. Front. 2022, 9, 1599. DOI: 10.1039/D2QO00013J). Gao-Qing Yuan of the South China University of Technology used electrolysis to promote the assembly of the pyrrole 12 by the coupling of the amino alcohol 10, the β-diketone 11, and the aldehyde 9 (Tetrahedron Lett. 2022, 90, 153615. DOI: 10.1016/j.tetlet.2021.153615).

Haiqing Luo of Gannan Normal University assembled the pyridine 15 by combining the enamide 13 with the maleimide 14 (Adv. Synth. Catal. 2022, 364, 1683. DOI: 10.1002/adsc.202200251). Jindian Duan of Nanjing Tech University combined the oxime ester 16 with 13, leading to the pyridine 17 (Synlett 2022, 33, 283. DOI: 10.1055/a-1679-7225). You Huang of Nankai University used a catalytic phosphine to promote the addition of the enamine 18 to the allene 19, to give after oxidation the pyridine 20 (Adv. Synth. Catal. 2022, 364, 1879. DOI: 10.1002/adsc.202200071). Yingjun Zhang of Sunshine Lake PharmaCompany and Huanfeng Jiang, also of the South China University of Technology, constructed the pyridine 23 by combining the hydrazone 21 with the azide 22 (J. Org. Chem. 2022, 87, 159. DOI: 10.1021/acs.joc.1c02086).

Zheyu Li, Chunran Zhang and Wenbo Ma of Chengdu University prepared the indole 26 by adding vinylidene carbonate 25 to the anilide 24 (Adv. Synth. Catal. 2022, 364, 838. DOI: 10.1002/adsc.202101466). Liangbin Huang, also of the South China University of Technology, used the Catellani protocol to construct the indole 29 from the iodobenzene 27 and the oxime acetate 28 (Org. Lett. 2022, 24, 484. DOI: 10.1021/acs.orglett.1c03679). Lu Bai and Xinjun Luan of Northwest University showed selective benzyl cleavage in the cyclization of the alkyne 30 with the hydroxylamine 31 to give the indole 32 (Angew. Chem. Int. Ed. 2022, 61, e202113820. DOI: 10.1002/anie.202113820). Mark D. Levin of the University of Chicago devised conditions to excise a carbon from the quinoline N-oxide 33, leading to the indole 34 (Science 2022, 376, 527. DOI: 10.1126/science.abo4282).

The alkaloid decursivine (37) was isolated from the creeping philodendron Rhaphidophora decursiva. Cheon-Gyu Cho of Hanyang University devised a route to 37 based on the intramolecular Fischer indole synthesis of 36 from the acetal 35 (Org. Lett. 2022, 24, 2873. DOI: 10.1021/acs.orglett.2c00848).