Metal-Mediated C-C Ring Construction: The Saicic/Bihelovic Synthesis of Platensimycin
Nicolai Cramer of the Ecole Polytechnique Fédérale de Lausanne devised a strategy for assembling the cyclopropane 4 by combining 1 first with 2, then with 3 (Chem. Sci. 2019, 10, 2773. DOI: 10.1039/C8SC05702H). Tomislav Rovis of Columbia University described related results (J. Am. Chem. Soc. 2019, 141, 6807. DOI: 10.1021/jacs.9b02156). Xiaohua Liu and Xiaoming Feng of Sichuan University prepared the cyclobutane 7 by adding 5 to 6 (Chem. Eur. J. 2018, 24, 19361. DOI: 10.1002/chem.201804600). Mu-Hyun Baik of KAIST and Tehshik P. Yoon of the University of Wisconsin reported a parallel investigation (J. Am. Chem. Soc. 2019, 141, 9543. DOI: 10.1021/jacs.9b04643).
Corinna S. Schindler of the University of Michigan found conditions for the cyclization of 8 to the cyclopentene 9 (carbonyl-alkene metathesis) (J. Am. Chem. Soc. 2019, 141, 1690. DOI: 10.1021/jacs.8b11840). Vy M. Dong of the University of California, Irvine reported the conversion of the racemic aldehyde 10 to the cyclopentanol 11 in high ee (Angew. Chem. Int. Ed. 2019, 58, 4705. DOI: 10.1002/anie.201900545). Gang Zhao of the Shanghai Institute of Organic Chemistry prepared 14 by adding 13 to 12 (Tetrahedron 2019, 75, 2706. DOI: 10.1016/j.tet.2019.03.045). Jan Vesely of Charles University assembled 17 by combining 15 with 16 (Chem. Commun. 2019, 55, 3829. DOI: 10.1039/C8CC06500D).
Phil S. Baran of Scripps/La Jolla devised a practical protocol for electrochemical Birch reduction, converting 18 to 19 (Science 2019, 363, 838. DOI: 10.1126/science.aav5606). Lukas S. Goossen of the Ruhr-Universität Bochum and Jin-Quan Yu, also of Scripps/La Jolla, established a strategy for coupling 20 with 21 to give either diastereomer of 22 in high ee (Chem. Eur. J. 2019, 25, 8503. DOI: 10.1002/chem.201902046). Stephen P. Fletcher of the University of Oxford prepared 25 by coupling 24, prepared from the corresponding alkene, with the prochiral 23 (Nature Commun. 2019, 10, 21. DOI: 10.1038/s41467-018-07871-x). Yoshihiro Sato of Hokkaido University cyclized the racemic allene 26 selectively to 27 (Org. Lett. 2019, 21, 4120. DOI: 10.1021/acs.orglett.9b01307).
Paul J. Chirik of Princeton University prepared the cyclooctadiene 30 by combining the diene 28 with the diene 29 (J. Am. Chem. Soc. 2019, 141, 8557. DOI: 10.1021/jacs.9b02443). Xiang Wu of the Hefei University of Technology used a Pd catalyst to cyclize 31, then couple that intermediate with 32, leading to 33 (Chem. Commun. 2019, 55, 3769. DOI: 10.1039/C9CC01379B).
Platensimycin (36), an antibiotic initially isolated from a strain of Streptomyces platensis, is in preclinical development for the treatment of MRSA. In the course of the preparation of a known intermediate in the total synthesis of 36, Radomir N. Saicic and Filip Bihelovic of the University of Belgrade devised the silver-mediated cyclization of 34 to 35 (Chem. Eur. J. 2019, 25, 4340. DOI: 10.1002/chem.201900497).