Organic Chemistry Portal
Organic Chemistry Highlights

Monday, June 8, 2020
Douglass F. Taber
University of Delaware

Benzene Derivatives: The Chen Synthesis of Glabralide B

Bing Sun and Fang-lin Zhang of the Wuhan University of Technology employed a catalytic aniline to mediate the ortho bromination of 1 to 2 (Tetrahedron Lett. 2019, 60, 151263. DOI: 10.1016/j.tetlet.2019.151263). Xin-Yan Wu and Qiong Li of the East China University of Science and Technology used a similar approach to prepare 5 by coupling 3 with 4 (Org. Lett. 2019, 21, 7342. DOI: acs.orglett.9b02632). Valerie A. Schmidt of the University of California, San Diego, rearranged 6 to 7 (Chem. Eur. J. 2019, 25, 15267. DOI: 10.1002/chem.201904288). Bartholomäus Pieber of the Max-Planck-Institute of Colloids and Interfaces used 8 to esterify 9, leading to 10 (Angew. Chem. Int. Ed. 2019, 58, 9575. DOI: 10.1002/anie.201902785). Hong-Xi Li and Jian-Ping Lang of Soochow University described a parallel investigation (Org. Chem. Front. 2019, 6, 2353. DOI: 10.1039/C9QO00536F).

Qingli Wang and Wanxiang Zhao of Hunan University developed the selective ortho cyanation of the phenol 11 with 12, to give 13 (Adv. Synth. Catal. 2019, 361, 4914. DOI: 10.1002/adsc.201900813). Jiean Chen and Yong Huang of Peking University Shenzhen Graduate School showed that the hydroxyethyl group of 14 was sufficient to mediate oxidative Heck coupling with 15, leading to 16 (Synlett 2019, 30, 1366. DOI: 10.1055/s-0037-1611538).

Manuel van Gemmeren of the Westfälische Wilhelms-Universität Münster observed significant regioselectivity in the alkynylation of 17 with 18 to give 19 (J. Am. Chem. Soc. 2019, 141, 18662. DOI: 10.1021/jacs.9b10868). Yingwei Zhao of Huaqiao University prepared 22 by coupling 20 with 21 (Adv. Synth. Catal. 2019, 361, 4674. DOI: 10.1002/adsc.201900804). Lukas J. Gooßen of Ruhr-Universität Bochum used 24 to convert 23 to the styrene 25 (Chem. Eur. J. 2019, 25, 8709. DOI: 10.1002/chem.201902022). Xiaoguang Lei of Peking University cyclized 26 with base and a Pd catalyst, then alkylated the product with methyl iodide, leading to 27 (Angew. Chem. Int. Ed. 2019, 58, 10879. DOI: 10.1002/anie.201903682).

Hai-Chao Xu of Xiamen University used electrolysis to cyclize 28 to 29 (Angew. Chem. Int. Ed. 2019, 58, 9017. DOI: 10.1002/anie.201904931). Chien-Wei Chiang and Aiwen Lei of Wuhan University constructed the biphenyl 32 by adding the thiophene 31 to the alkyne 30 (Angew. Chem. Int. Ed. 2019, 58, 12206. DOI: 10.1002/anie.201905971).

Glabralide B (36) isolated from the Southeast Asian medicinal herb Sarcandra glabra, is structurally related to other natural products that show anti-HIV activity. In the course of a synthesis of 36, Ji-Jun Chen of the Kunming Institute of Botany prepared 35 by directly alkylating the phenol 33 with geranyl bromide 34 (Tetrahedron Lett. 2019, 60, 151059. DOI: 10.1016/j.tetlet.2019.151059).

D. F. Taber, Org. Chem. Highlights 2020, June 8.