Arrays of Stereogenic Centers: The Liu Synthesis of Shizukaol J
Shyam Sathyamoorthi of the University of Kansas showed that the epoxide 1 could be cyclized to the differentially-protected triol 2 (Org. Lett. 2022, 24, 939. DOI: 10.1021/acs.orglett.1c04310). David J. Aitken of the Universitť Paris-Saclay assembled the ester 5 by adding the protected cyanohydrin 4 to the α-amino aldehyde 3 (Org. Biomol. Chem. 2022, 20, 1769. DOI: 10.1039/D1OB02411F). Alison E. Wendlandt of MIT devised the photochemically-promoted equilibration of the cis diol 6 to the trans diol 7 (J. Am. Chem. Soc. 2022, 144, 599. DOI: 10.1021/jacs.1c11902). David W. C. MacMillan of Princeton University (J. Am. Chem. Soc. 2022, 144, 93. DOI: 10.1021/jacs.1c11552) and Weiping Tang of the University of Wisconsin (J. Am. Chem. Soc. 2022, 144, 3727. DOI: 10.1021/jacs.1c13399) reported complentary protocols for converting trans diols to cis diols. Yoshitaka Hamashima of the University of Shizuoka cyclized the prochiral amide 8 to the bromide 9 (J. Am. Chem. Soc. 2022, 144, 3913. DOI: 10.1021/jacs.1c11816).
Peng Liu of the University of Pittsburgh and Ming-Yu Ngai of the State University of New York, Stony Brook coupled the glycosyl bromide 10 with styrene 11 to give the alkene 12 (J. Am. Chem. Soc. 2022, 144, 3353. DOI: 10.1021/jacs.1c13299). Xiaolei Wang of Lanzhou University alkylated the protected glycine ester 14 with the allylic carbonate 13 to give the branched product 15 (Synlett 2022, 33, 655. DOI: 10.1055/s-0040-1719909). Jun Zheng and Bernhard Breit of the Albert-Ludwigs-Universitšt Freiburg devised the photochemically-promoted addition of the α-amino acid derivative 17 to the diene 16, leading to the tertiary ether 18 (Angew. Chem. Int. Ed. 2022, 61, e202200105. DOI: 10.1002/anie.202200105). Yuichiro Kawamoto and Hisanaka Ito of the Tokyo University of Pharmacy and Life Sciences observed that reduction of the epoxide 19 proceeded with clean inversion, to give the diol 20 (Tetrahedron 2022, 106-107, 132595. DOI: 10.1016/j.tet.2021.132595).
Martin Hiersemann of TU Dortmund used a Cu catalyst to rearrange the alkenyl ether 21 to the α-keto ester 22 (Chem. Eur. J. 2022, 28, e202103558. DOI: 10.1002/chem.202103558). Hayato Ishikawa of Chiba University used the JÝrgenson-Hayashi catalyst to mediate the three-component coupling of the alkynyl aldehyde 23, the thioester 24 and the aldehyde 25 to give the ester 26 (Chem. Eur. J. 2022, 28, e202104052. DOI: 10.1002/chem.202104052). Kannupal Srinivasan of Barathidasan University observed clean stereocontrol in the rearrangement of the cyclopropane 27 to the lactone 28 (Org. Biomol. Chem. 2022, 20, 3145. DOI: 10.1039/D2OB00292B). Ilan Marek of Technion-Israel Institute of Technology established the acyclic quaternary center of the diene 30 by opening the cyclopropane 29 (J. Am. Chem. Soc. 2022, 144, 7066. DOI: 10.1021/jacs.2c01695).
The dimeric sesquiterpenoid shizukaol J (33) was isolated from the herb Chloranthus fortunei, used in Chinese folk medicine for the treatment of bone fractures. Early in a synthesis of 33, Bo Liu of Sichuan University demonstrated the efficient construction of 32 by alkylation of the β-lactone 31 (Angew. Chem. Int. Ed. 2022, 61, e202200258. DOI: 10.1002/anie.202200258).