Monday, June 18, 2018
Douglass F. Taber
University of Delaware
Substituted Benzene Derivatives: The Barrett Synthesis of Grifolic Acid
Lu Liu and Junliang Zhang of East China Normal University used a gold catalyst to selectively add the diazo ester 2 to the para position of 1, leading to 3 (Chem. Commun. 2017, 53, 10164. ). Ganesh Pandey of the Centre of Bio-Medical Research observed high para selectivity in the preparation of 6 by the photochemically-mediated addition of the selenide 5 to 4 (Chem. Commun. 2017, 53, 12337. ).
Graham E. Dobereiner of Temple University showed that metal triflates accelerated the Pd-catalyzed coupling of an amide 8 with an aryl halide 7 to give the acetanilide 9 (ACS Catal. 2017, 7, 5862. ). Yoshiaki Nakao of Kyoto University assembled the arylamine 12 by displacing the nitro group of 10 with the amine 11 (Angew. Chem. Int. Ed. 2017, 56, 13307. ).
Jianhong Zhao of the East China University of Science and Technology and Hegui Gong of Shanghai University prepared 15 by coupling the aryl tosylate 13 with methyl tosylate 14 (Chem. Commun. 2017, 53, 10180. ). Sachin Handa of the University of Louisville devised a surfactant that promoted the Pd-mediated coupling of the nitroalkane 17 with 16 to give 18 (ACS Catal. 2017, 7, 7245. ).
Yuguo Zheng and Qing Zhu of the Zhejiang University of Technology established a simple protocol for the ortho azidation of an aniline derivative 19, leading to 20 (J. Org. Chem. 2017, 82, 11212. ). David A. Nicewicz of the University of North Carolina found that the photochemically-mediated amination of 21 with 22 also proceeded with high ortho selectivity, to give 23 (Angew. Chem. Int. Ed. 2017, 56, 15644, ; J. Am. Chem. Soc. 2017, 139, 16100, .).
Keith H. Pannell of the University of Texas at El Paso demonstrated that 25, readily prepared by reduction of dimethylformamide, reacted spontaneously with a phenol 24 to give the o-quinone methide precursor 26 (Eur. J. Org. Chem. 2017, 5610. ). Xiuli Zhang of Anhui Agricultural University developed a protocol for the ortho acylation of a phenol 27 with a nitrile 28 to give the benzophenone 29 (Tetrahedron Lett. 2017, 58, 4197. ).
Nagatoshi Nishiwaki of the Kochi University of Technology assembled the aniline 32 by combining 30 with the ester 31 (Tetrahedron Lett. 2017, 58, 4699. ). Xiaoming Jie and Weiping Su of the Fujian Institute of Research on the Structure of Matter aromatized 33 directly to the benzaldehyde 34 (Nature Commun. 2017, 8, 2273. ).
Grifolic acid (38) is a selective partial agonist of GPR120 that induces ERK activation and intracellular calcium responses in mouse enteroendocrine STC-1 cells. Anthony G. M. Barrett of Imperial College developed a Pd-mediated cyclization that converted the farnesyl ester 35, first activated by acylation with 36, to the substituted resorcinol 37 (Tetrahedron Lett. 2017, 58, 2765. ).
D. F. Taber, Org. Chem. Highlights 2018, June 18.