Kinetics and Mechanism of the Aminolysis of O-Methyl S-Aryl Thiocarbonates in Acetonitrile
作者:Hyuck-Keun Oh
DOI:10.5012/bkcs.2011.32.5.1539
日期:2011.5.20
The aminolysis of O-methyl S-aryl thiocarbonates with benzylamines are studied in acetonitrile at -45.0. The () values are in the range 0.62-0.80 with a negative cross-interaction constant, = -0.42, which are interpreted to indicate a concerted mechanism. The kinetic isotope effects involving deuterated benzylamine nucleophiles () are large, = 1.29-1.75, suggesting that the N-H(D) bond is partially
Hofmann Rearrangement of Carboxamides Mediated by Hypervalent Iodine Species Generated in Situ from Iodobenzene and Oxone: Reaction Scope and Limitations
作者:Aleksandra A. Zagulyaeva、Christopher T. Banek、Mekhman S. Yusubov、Viktor V. Zhdankin
DOI:10.1021/ol101993q
日期:2010.10.15
Alkylcarboxamides can be converted to the respective amines by Hofmann rearrangement using hypervalent iodine species generated in situ from PhI and Oxone in aqueous acetonitrile. On the basis of this reaction, a convenient experimental procedure for the preparation of alkylcarbamates using Oxone as the oxidant in the presence of iodobenzene in methanol has been developed. An efficient method for direct
Molecularoxygen serves as a useful oxidant for the glycol scission of 1,2-diols and the Hofmann rearrangement of primary amides using pentamethyliodobenzene as a catalyst. The use of isobutyraldehyde and Lewis basic nitriles under O2 enabled the iodine(I)/(III) catalytic cycle, where in situ-generated peracid acts as a terminal oxidant.
Practical Metal-Free C(sp<sup>3</sup>)H Functionalization: Construction of Structurally Diverse α-Substituted<i>N</i>-Benzyl and<i>N</i>-Allyl Carbamates
is a practical and universal CH functionalization of readily removable N‐benzyl and N‐allyl carbamates, with a wide range of nucleophiles at ambient temperature promoted by Ph3CClO4. The metal‐free reaction has an excellent functional‐group tolerance, and displays a broad scope with respect to both N‐carbamates and nucleophile partners (a variety of organoboranes and CH compounds). The synthetic utility
Urethanes synthesis from oxamic acids under electrochemical conditions
作者:Ikechukwu Martin Ogbu、Jonathan Lusseau、Gülbin Kurtay、Frédéric Robert、Yannick Landais
DOI:10.1039/d0cc05069e
日期:——
Urethanesynthesis via oxidative decarboxylation of oxamic acids under mild electrochemical conditions is reported. This simple phosgene-free route to urethanes involves an in situ generation of isocyanates by anodic oxidation of oxamic acids in an alcoholic medium. The reaction is applicable to a wide range of oxamic acids, including chiral ones, and alcohols furnishing the desired urethanes in a