Organic Chemistry Portal
Organic Chemistry Highlights

Monday, October 22, 2018
Douglass F. Taber
University of Delaware

C-C Bond Construction: The Mori Synthesis of the Pheromone of the Red-Necked Longhorn Beetle

Troels Skrydstrup of Aahus University prepared the ketone 3 by coupling 1 and 2 with carbon monoxide (Angew. Chem. Int. Ed. 2018, 57, 800. DOI: 10.1002/anie.201710089). Takashi Nishikata of Yamaguchi University assembled the quaternary center of 6 by adding 4 to the enamide 5 (Chem. Eur. J. 2018, 24, 6354. DOI: 10.1002/chem.201801065). Jia-Rong Chen and Wen-Jing Xiao of Central China Normal University fragmented the oxime 8 and added the resulting radical to 7, leading to 9 (Angew. Chem. Int. Ed. 2018, 57, 738. DOI: 10.1002/anie.201710618). Daniele Leonori of the University of Manchester (Angew. Chem. Int. Ed. 2018, 57, 744. DOI: 10.1002/anie.201710790) and Li-Na Guo of Xi'an Jiaotong University (Adv. Synth. Catal. 2018, 360, 1775, DOI: 10.1002/adsc.201701630; J. Org. Chem. 2018, 83, 4239, DOI: 10.1021/acs.joc.8b00271) reported related results. Joyram Guin of the Indian Association for the Cultivation of Science devised the oxidative decarbonylation of 11 and ensuing radical addition to 10 that led to 12 (J. Org. Chem. 2018, 83, 5629. DOI: 10.1021/acs.joc.8b00618).

Lelia Cosimbescu of the Pacific Northwest Regional Laboratory allylated 11 by warming it with 13, to give 14 (Tetrahedron Lett. 2018, 59, 1421. DOI: 10.1016/j.tetlet.2018.02.073). Yuanhong Liu of the Shanghai Institute of Organic Chemistry converted the alkyne 15 to the branched nitrile 16 (J. Am. Chem. Soc. 2018, 140, 7385. DOI: 10.1021/jacs.8b02542). Lionel Perrin of Université Claude Bernard 1, Odile Eisenstein of Université de Montpellier and Ilan Marek of Technion-Israel Institute of Technology opened the cyclopropane 17 with dibutyl zirconocene to give an intermediate to which they added sequentially acetone (18) and iodine, leading to the alcohol 19 with remarkable diastereocontrol (J. Org. Chem. 2018, 83, 3497. DOI: 10.1021/acs.joc.7b03115). Yun-He Xu and Teck-Peng Loh of the University of Science and Technology of China closed the macrocycle 21 by Rh-catalyzed oxidation of the simple acrylate 20 (Angew. Chem. Int. Ed. 2018, 57, 555. DOI: 10.1002/anie.201710601).

Tohru Oishi of Kyushu University opened the epoxide 22 with the readily-prepared dianion 23, leading to homopropargylic alcohol 24 (Angew. Chem. Int. Ed. 2018, 57, 6060. DOI: 10.1002/anie.201712167). Weisheng Tian and Jinghan Gui, also of the Shanghai Institute of Organic Chemistry, prepared the alkyne 26 by oxidative cleavage of the furan 25 (Angew. Chem. Int. Ed. 2018, 57, 3617. DOI: 10.1002/anie.201712365).

Mariappan Periasamy of the University of Hyderabad used 29 to mediate the coupling of 27 with 28 to give the allene 30 (J. Org. Chem. 2018, 83, 267. DOI: 10.1021/acs.joc.7b02632). Sebastian Torker and Amir H. Hoveyda of Boston College added (pin)BH to 31 to give an intermediate that was then coupled with iodobenzene to give 32 (J. Am. Chem. Soc. 2018, 140, 2643. DOI: 10.1021/jacs.7b13296). Shaozhong Ge of the National University of Singapore (Org. Chem. Front. 2018, 5, 1284) and Keary M. Engle of Scripps-La Jolla (ACS Catal. 2018, 8, 3650. DOI: 10.1021/acscatal.8b00626) reported related results.

The red-necked longhorn beetle Aromia bungii is a serious threat to the fruit industry of lowland China. A key step in the synthesis of the pheromone 36 of this beetle accomplished by Kenji Mori of Toyo Gosei Co. was the selective coupling of the allyl Grignard reagent 34 with the triflate 33 to give 35 (Tetrahedron 2018, 74, 1444. DOI: 10.1016/j.tet.2018.01.052).

D. F. Taber, Org. Chem. Highlights 2018, October 22.