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51.
Zhiyuan Huang Zaki K. Phelan Rachel L. Tritt Shelby D. Valent Daniel R. Griffith 《Tetrahedron letters》2018,59(37):3432-3434
A formal aza-Michael addition to tropone by way of tricarbonyl(tropone)iron and/or the tetrafluoroborate salt formed via protonation of the complex is reported. Tricarbonyl(tropone)iron smoothly undergoes the direct aza-Michael reaction with unhindered aliphatic amines under solvent free conditions in good yields. Meanwhile, the known cationic complex [(C7H7O)Fe(CO)3]BF4 (whose reaction with a small number of nucleophiles was previously reported) undergoes addition with an even broader array of amine nucleophiles. Finally, it was discovered that protecting the aza-Michael adduct as a carbamate was necessary for oxidative demetallation of the complex. 相似文献
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Bulten HJ Anthony PL Arnold RG Arrington J Beise EJ Belz E van Bibber K Bosted PE van den Brand JF Chapman MS Coulter KP Dietrich FS Ent R Epstein M Filippone BW Gao H Gearhart RA Geesaman DF Hansen J Holt RJ Jackson HE Jones CE Keppel CE Kinney E Kuhn SE Lee K Lorenzon W Lung A Makins NC Margaziotis DJ McKeown RD Milner RG Mueller B Napolitano J Nelson J O'Neill TG Papavassiliou V Petratos GG Potterveld DH Rock SE Spengos M Szalata ZM Tao LH White JL Zeidman B 《Physical review letters》1995,74(24):4775-4778
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Audouard C Barsukov I Fawcett J Griffith GA Percy JM Pintat S Smith CA 《Chemical communications (Cambridge, England)》2004,(13):1526-1527
A (bromodifluoromethyl)alkyne has been deployed in a stereoselective route to difluorinated aldonic acid analogues, in which a Sharpless asymmetric dihydroxylation reaction and diastereoisomer separation set the stage for phenyl group oxidation. 相似文献
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Andrew C. Dengel Ahmed M. El-Hendawy William P. Griffith Andrew D. White 《Transition Metal Chemistry》1989,14(3):230-232
Summary The osmium(VII) salt (Ph4P)[OsO4] functions as a stoichiometric oxidant for benzylic and allylic alcohols, oxidising primary alcohols to aldehydes and secondary alcohols to ketones. Its vibrational spectra and cyclic voltammetric behaviour are compared with those of the perruthenate ion, [RuO4]–. 相似文献
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Oh-Kil Kim James R. Griffith 《Journal of polymer science. Part A, Polymer chemistry》1975,13(1):151-160
Acrylamide graft copolymerization onto poly(3-O-methacryloyl D -glucose) (PMG) as a backbone was performed by the ceric ion method. The number of polyacrylamide (PAM) chains grafted was dependent upon the concentration ratio of the redox catalyst system at constant acid concentration and increased in proportion to the ceric ion concentration. A maximum number of grafts obtained, for example, was 29 onto PMG (DP = 244) under the conditions [Ce4+]/[PMG] = 1/5, [H+] = 1.0 × 10?2 mole/l. In other words, the graft frequency was 12 per 100 monomer units of PMG. Such a high frequency of the grafts was, however, greatly decreased when the acid concentration was increased. Characteristics of the highly branched structure were revealed by the relationship between intrinsic viscosity and graft frequency, which showed a downward curvature with the increasing graft frequency. Influences of acid and ceric ion concentrations on the copolymerization were kinetically evaluated. The rate of polymerization was found to be first-order with respect to ceric ion and proportional to the square of the reciprocal acid concentration. The result suggests that the graft frequency is dependent upon the rate of polymerization. 相似文献
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