Organic Chemistry Portal
Organic Chemistry Highlights

Monday, March 11, 2024
Douglass F. Taber
University of Delaware

Functional Group Interconversion: The Nagasawa/Iwabuchi Synthesis of Rumphellclovane E

Christopher B. Kelly of Janssen Discovery Process, Osvaldo Gutierrez of Texas A&M and Mark D. Levin of the University of Chicago used the N-acyloxy N-alkoxy amide 2 to convert the primary amine 1 to the corresonding bromide 3 (J. Am. Chem. Soc. 2023, 145, 17. DOI: 10.1021/jacs.2c11453). Xu Yao of the University of South China and Jin-Hong Lin and Ji-Chang Xiao of the Shanghai Institute of Organic Chemistry prepared the sulfone 6 by coupling the primary alcohol 4 with the arenesulfinate 5 (J. Org. Chem. 2023, 88, 4818. DOI: 10.1021/acs.joc.2c03085). Shuanglin Qu of Hunan University and Bo Zhang of China Pharmaceutical University added the arenesulfonyl chloride 8 to the alkyne 7, leading to the (Z)-unsaturated sulfone 9 (ACS Catal. 2023, 13, 6983. DOI: 10.1021/acscatal.3c01529). Bill Morandi of ETH Zürich used a Rh catalyst to convert the alkyne 10 to the (Z)-alkenyl iodide 11 (Angew. Chem. Int. Ed. 2023, 62, e202214071. DOI: 10.1002/anie.202214071).

Do Hyun Ryu of Sungkyunkwan University and Hui Jin and Lixin Zhang of the Shenyang University of Chemical Technology developed conditions for preparing the cyanomethyl amine 13 from the secondary amine 12 (Adv. Synth. Catal. 2023, 365, 2. DOI: 10.1002/adsc.202200767). Carsten Bolm of RWTH Aachen University used visible light to promote the Wolff rearrangement of the diazo ketone 14, leading to a ketene that acylated the sulfonimidamide 15, to give 16 (Adv. Synth. Catal. 2023, 365, 31. DOI: 10.1002/adsc.202201274).

Alessandro Palmieri of the University of Camerino converted the readily-prepared nitro ketone 17 into the diene 18 (Adv. Synth. Catal. 2023, 365, 13. DOI: 10.1002/adsc.202201151). Sebastien Stecko of the Institute of Organic Chemistry of the Polish Academy of Sciences showed that Wacker oxidation of the allylic amine 19 proceeded with high regioselectivity to give the ketone 20 (Org. Biomol. Chem. 2023, 21, 115. DOI: 10.1039/D2OB01843H). Similar results have been achieved with allylic ethers (Reactions of Alkenes: The Christmann Synthesis of Spongidine A 2020, November 23).

In the course of a synthesis of asperaculin A, Hisanaka Ito of the Tokyo University of Pharmacy and Life Sciences used a Pd catalyst to convert the very hindered nitrile 21 to the amide 22 (Org. Lett. 2023, 25, 4510. DOI: 10.1021/acs.orglett.3c01530). Christoforos G. Kokotos and George Kokotos of the National and Kapodistrian University of Athens acylated the protected hydroxylamine 24 with the acid 23, leading to the protected hydroxamic acid 25 (Eur. J. Org. Chem. 2023, 26, e202300046, DOI: 10.1002/ejoc.202300046; e202300008, DOI: 10.1002/ejoc.202300008). Wen Hu of of Chongqing University used a 2,2'-bipyridinium salt to promote the Ritter coupling of the alcohol 27 with the nitrile 26, to give the amide 28 (J. Org. Chem. 2023, 88, 4066. DOI: 10.1021/acs.joc.2c02239). Hemchandra Chaudhari of the Institute of Chemical Technology used N-chloro-N-(phenylsulfonylbenzenesulfonamide 30 to convert the N-alkoxy amide 29 to the ester 31 (Tetrahedron Lett. 2023, 123, 154539. DOI: 10.1016/j.tetlet.2023.154539).

Rumphellclovane E (34) was isolated from the gorgonian coral Rumphella antipathies. En route to 34, Shota Nagasawa and Yoshiharu Iwabuchi of Tohoku University effected the selective conversion of the alkyne 32 to the aldehyde 33 (Org. Lett. 2022, 24, 7572. DOI: 10.1021/acs.orglett.2c02960).

D. F. Taber, Org. Chem. Highlights 2024, March 11.