Organic Chemistry Portal
Organic Chemistry Highlights

Monday, July 30, 2018
Douglass F. Taber
University of Delaware

Organocatalyzed C-C Ring Construction: The Scheidt Synthesis of Armillaridin

M. Kevin Brown of Indiana University found that the combination of high ee starting material 1 and an enantioselective organocatalyst was required to achieve high ee in the preparation of 2 (Org. Lett. 2017, 19, 3703. DOI: 10.1021/acs.orglett.7b01420). Nisar Ullah of King Fahd University of Petroleum and Materials, Yu Lan of Chongqing University and Yixin Lu of the National University of Singapore cyclized 3 to the cyclopentene 4 (Chem. Sci. 2017, 8, 5196. DOI: 10.1039/C7SC00952F).

Frank Hollmann of the Delft University of Technology and Chan Beum Park of KAIST devised a photochemically-driven enzymatic reduction of 5 to 6 (Angew. Chem. Int. Ed. 2017, 56, 8681. DOI: 10.1002/anie.201702461). Ying-Chun Chen of Sichuan University added 8 to the prochiral 7, leading to 9 (Chem. Eur. J. 2017, 23, 10678. DOI: 10.1002/chem.201702183). Xiaoming Feng, also of Sichuan University, developed an organocatalyst for the ene reaction of 11 with prochiral 10 to give 12 (Org. Lett. 2017, 19, 3374. DOI: 10.1021/acs.orglett.7b01329). You Huang of Nankai University (Org. Biomol. Chem. 2017, 15, 7097. DOI: 10.1039/C7OB01820G) and Shinobu Takizawa and Hiroaki Sasai of Osaka University (Chem. Commun. 2017, 53, 7724. DOI: 10.1039/C7CC02839C) independently established conditions for the Rauhut-Currier cyclization of 13 to 14. Łukasz Albrecht of the Lodz University of Technology constructed 17 by adding 15 to 16 (Org. Lett. 2017, 19, 3143. DOI: 10.1021/acs.orglett.7b01268). Xinqiang Fang of the Fujian Institute of Research on the Structure of Matter added 18 to 19 to give 20 (Chem. Commun. 2017, 53, 13336. DOI: 10.1039/C7CC08680F).

Subhas Chandra Pan of the Indian Institute of Technology Guwahati Assam assembled the bicyclic 23 by combining 21 with 22 (Eur. J. Org. Chem. 2017, 6457. DOI: 10.1002/ejoc.201701238). Xiu-Qin Dong and Chun-Jiang Wang of Wuhan University added 24 to 25, leading to the tricyclic 26 (Org. Lett. 2017, 19, 4532. DOI: 10.1021/acs.orglett.7b02107). Yujiro Hayashi of Tohoku University prepared the ACD steroid precursor 29 by adding 28 to 27 (Angew. Chem. Int. Ed. 2017, 56, 11812. DOI: 10.1002/anie.201706046). Eric N. Jacobsen of Harvard University developed the dipolar cycloaddition of 31 to 30, leading to 32 (Science 2017, 358, 761. DOI: 10.1126/science.aao5894). Michael Harmata of the University of Missouri (Org. Lett. 2017, 19, 4106. DOI: 10.1021/acs.orglett.7b01868) and Uxue Uria and Josť L. Vicario of the University of the Basque Country (Angew. Chem. Int. Ed. 2017, 56, 10535. DOI: 10.1002/anie.201704804) reported parallel investigations.

Armillaridin (35), isolated from the honey mushroom Armillaria mellea, inhibits the activation and differentiation of human macrophages. En route to 35, Karl A. Scheidt of Northwestern University achieved high enantioselectivity in the organocatalyzed cyclization of 33 to 34 (Angew. Chem. Int. Ed. 2017, 56, 9864. DOI: 10.1002/anie.201705308).

D. F. Taber, Org. Chem. Highlights 2018, July 30.