Reduction: The Hayashi Synthesis of Estradiol Methyl Ether

Ramakrishna G. Bhat of the Indian Institute of Science Education and Research reduced 1 to 2, preserving the two aryl bromides (Tetrahedron Lett. 2018, 59, 3288. DOI: 10.1016/j.tetlet.2018.07.041). Montserrat Gómez of the Université de Toulouse semihydrogenated the alkyne of 3 to the E-alkene 4, without affecting the terminal vinyl group (Adv. Synth. Catal. 2018, 360, 3544. DOI: 10.1002/adsc.201800786). Kendall N. Houk of UCLA and Zhuangzhi Shi of Nanjing University devised the selective opening of the cyclopropane 5 to the boronic ester 6 (Angew. Chem. Int. Ed. 2018, 57, 16861. DOI: 10.1002/anie.201811036). Stephen Philip Fearnley of the City University of New York, York College effected the reductive opening of 7 to 8 (Tetrahedron Lett. 2018, 59, 3528. DOI: 10.1016/j.tetlet.2018.08.020).

Igor M. Opsenica of the University of Belgrade optimized the Pd-catalyzed decarbonylation of 9 to 10 (Synlett 2018, 29, 1781. DOI: 10.1055/s-0037-1610433). Ying-Ming Pan of Guangxi Normal University and Yun-Jie Ding of the Dalian Institute of Chemical Physics described related results (Chem. Commun. 2018, 54, 8446. DOI: 10.1039/C8CC03109F). Naoto Chatani and Mamoru Tobisu of Osaka University reduced the aryl ether 11 to the arene 12 (ACS Catal. 2018, 8, 7475. DOI: 10.1021/acscatal.8b02009). Paul J. Dyson of the Ecole Polytechnique Fédérale de Lausanne reported the complementary reduction, of 13 to 14 (Chem. Sci. 2018, 9, 5530. DOI: 10.1039/C8SC00742J). Walter Leitner of RWTH Aachen University used used a bifunctional Fe/Ru catalyst to reduce the keton 15 to the alkane 16 (Angew. Chem. Int. Ed. 2018, 57, 12721. DOI: 10.1002/anie.201806638).

Matthias Beller and Rajenahally V. Jagadeesh of the Universität Rostock devised a protocol for reducing a ketone 17 to the primary amine 18 (Nature Commun. 2018, 9, 4123. DOI: 10.1038/s41467-018-06416-6). Zhimin Liu of the Institute of Chemistry, Chinese Academy of Sciences assembled 21 by combining the aldehyde 19 with the amine 20 (Org. Lett. 2018, 20, 6622. DOI: 10.1021/acs.orglett.8b02384). Junling Guo and Neel S. Joshi of Harvard University coated yeast cells with In nanoparticles, leading to a system that generated NADH on exposure to light, and so enabled the production and reduction of 22 to shikimic acid (23) (Science 2018, 362, 813. DOI: 10.1126/science.aat9777). Ursula Biermann of the University of Oldenburg and Michael A. R. Meier of the Karlsruhe Institute of Technology developed a reagent combination for the reduction of a polyester 24 to the polyether 25 (Angew. Chem. Int. Ed. 2018, 57, 8775. DOI: 10.1002/anie.201804368).

In an elegant organocatalyzed approach to estradiol methyl ether 28, Yujiro Hayashi of Tohoku University prepared the carboxylic acid 26. The last stereogenic center was then set by hydrogenation to 27 (Eur. J. Org. Chem. 2018, 5629. DOI: 10.1002/ejoc.201800910).