Monday, May 29, 2017
Douglass F. Taber
University of Delaware
Interconversion of Organic Functional Groups
David B. Collum of Cornell University developed (J. Org. Chem. 2016, 81, 11312. ) sodium diisopropylamide as a useful reagent for many base-mediated transformations, including the conversion of 1 to 2. Seth B. Herzon of Yale University devised (J. Org. Chem. 2016, 81, 8673. ) oxidative conditions for the net hydrolysis of an alkenyl halide 3 to the ketone 4. Alkenyl sulfides and alkenyl silanes were also converted to ketones. Graham E. Dobereiner of Temple University observed (Adv. Synth. Catal. 2016, 358, 4106. ) substantial regioselectivity in the Au-mediated hydration of the alkyne 5 to the ketone 6. Janez Kosmrlj of the University of Ljubljana and Tsuyoshi Taniguchi of Kanazawa University described (Chem. Sci. 2016, 7, 5148. ) in more detail the Mitsunobu conversion of 7 to 9 using catalytic 8, but cast doubt (Org. Lett. 2016, 18, 4036. ) on the previously-described ( 2016, May 30) "fully catalytic" Mitsunobu reaction.
Belén Martín-Matute of Stockholm University optimized (Chem. Eur. J. 2016, 22, 15659. ) the Ir-mediated conversion of 10 to 11. Clément Mazet of the University of Geneva demonstrated (J. Am. Chem. Soc. 2016, 138, 10344. ) that 12 was isomerized smoothly to 13, the Pd-mediated bond migration having successfully traversed the alkylated stereogenic center.
Petri M. Pihko of the University of Jyväskylä effected (Synlett 2016, 27, 1649. ) the net reductive hydration of the enal 14 to the diol 15. John F. Hartwig of the University of California, Berkeley established (ACS Central Sci. 2016, 2, 647. ) conditions for the selective coupling of the tertiary bromide of 16 with 17 to give 18.
Liang-Nian He of Nankai University showed (Chem. Eur. J. 2016, 22, 16489. ) that CO2 could be used to methylate the amine 19, leading to 20. Peipei Sun of Nanjing Normal University opened (Org. Biomol. Chem. 2016, 14, 7018. ) the amine 21 with TsCl and a copper catalyst to give 22. Hiroaki Tsuji and Hisashi Yamamoto of Chubu University developed (J. Am. Chem. Soc. 2016, 138, 14218. ) Ta ethoxide as a specific catalyst for the amination of the β-hydroxy ester of 23 with 24 to give the amide 25. Junfeng Zhao of Jiangxi Normal University demonstrated (J. Am. Chem. Soc. 2016, 138, 13135. ) that using 28 as the coupling reagent, 29 could be prepared from 26 and 27 with no observable epimerization.
Several years ago, we observed that a bromide such as 31 prepared from 30 using Br2/Ph3P would not form the Grignard reagent. After bulb-to-bulb distillation of 31, the Grignard formed readily. We did not originate this - does anyone have the reference?
D. F. Taber, Org. Chem. Highlights 2017, May 29.