Organic Chemistry Portal
Organic Chemistry Highlights

Monday, April 29, 2024
Douglass F. Taber
University of Delaware

Carbon-Carbon Bond Formation: The Aggarwal Synthesis of 10-Deoxymethynolide

Wenbo H. Liu of Sun Yat-sen University prepared the alcohol 3 by coupling the pyridinium salt 1 with the aldehyde 2 (Org. Lett. 2023, 25, 4934. DOI: 10.1021/acs.orglett.3c01724). Gregory C. Fu of Caltech showed that under iron catalysis, migration of the alkene of 4 preceded carbon-carbon formation with the iodide 5, leading to the linear product 6 (Angew. Chem. Int. Ed. 2023, 62, e202306663. DOI: 10.1002/anie.202306663). Marc Presset and Erwan Le Gall of Univ Paris Est Creteil assembled the β-keto ester 10 by adding the alkyl iodozinc 9 in a conjugate sense to methyl acrylate 7 in the presence of the acid chloride 8 (Adv. Synth. Catal. 2023, 365, 2877. DOI: 10.1002/adsc.202300540). David W. C. MacMillan of Princeton University activated the tertiary alcohol 11 by coupling with the benzoxazolium salt 12, then coupled that product with the alkyl bromide 13 in the presence of the N-hydroxyphthalimide derivative 14, establishing the cyclic quaternary center of 15 (J. Am. Chem. Soc. 2023, 145, 16330. DOI: 10.1021/jacs.3c05405).

Jon A. Tunge of the University of Kansas effected the decarboxylative allylation of the α-nitro ester 16, leading to the α-quaternary nitroalkane 17 (Chem. Eur. J. 2023, 29, e202302174. DOI: 10.1002/chem.202302174). Nianki Fu of the Institute of Chemistry of the Chinese Academy of Sciences prepared the α-amino ester 20 by decarboxylative coupling of the carboxylic acid 18 with the bromoalkene 19 (J. Am. Chem. Soc. 2023, 145, 26774. DOI: 10.1021/jacs.3c08839). Jaideep Saha of the National Institute of Pharmaceutical Education and Research devised the ring-opening addition of the activated cyclopropane 22 to the alkene 21, leading to 23 (Org. Lett. 2023, 25, 5676. DOI: 10.1021/acs.orglett.3c02105). Hongjian Lu of Nanjing University prepared the diene 25 by the oxidative removal of nitrogen from the pyrrolidine 24 (Nature Commun. 2023, 14, 7307. DOI: 10.1038/s41467-023-43238-7).

Marius M. Haugland of the Arctic University of Norway converted the protected iodohydrin 26 to the alkyne 27 (J. Org. Chem. 2023, 88, 12451. DOI: 10.1021/acs.joc.3c01213). Cheng-Zhi Gu of Shihezi University and Xinqiang Fang of the Fujian Institute of Research on the Structure of Matter achieved high diasteroselectivity and enantioselectivity in the preparation of the alcohol 30 by the addition of the propargylic carbonate 29 to the aldehyde 28 (J. Am. Chem. Soc. 2023, 145, 27539. DOI: 10.1021/jacs.3c09155).

Zhihui Shao of Yunnan University used a Pd catalyst to couple the prochiral allene 31 with the sulfonamide 32, leading to the allene 33 in high ee (Chem. Sci. 2023, 14, 10812. DOI: 10.1039/D3SC04581A). Almost thirty years ago, Andrew G. Myers, now at Harvard University, described the simple conversion of the propargyl alcohol 34 to the allene 35 (J. Am. Chem. Soc. 1996, 118, 4492. DOI: 10.1021/ja960443w).

The antibiotic 10-deoxymethynolide (39) was isolated from the soil-dwelling Gram-positive bacterium Streptomyces venezuelae. Varinder K. Aggarwal of the University of Bristol developed a new route to 39 based on the coupling of the borane 36 with lithiated methoxyallene 37 to give the enone 38 (Angew. Chem. Int. Ed. 2023, 62, e202312054. DOI: 10.1002/anie.202312054).

D. F. Taber, Org. Chem. Highlights 2024, April 29.