22276-28-4Relevant academic research and scientific papers
Acid-promoted rearrangement of arylmethyl azides: Applications toward the synthesis of N-arylmethyl arenes and polycyclic heteroaromatic compounds
Tummatorn, Jumreang,Thongsornkleeb, Charnsak,Ruchirawat, Somsak
experimental part, p. 4732 - 4739 (2012/07/28)
An acid-promoted Aubé-Schmidt's rearrangement of arylmethyl azides provides a useful in situ iminium ion intermediate, which can be efficiently trapped by various nucleophiles. We report here the reaction of this iminium ion with aromatic nucleophiles to
Remote Pummerer Reaction via Intermolecular Through-Space Interaction between Sulfonium and Sulfenyl Sulfur Atoms
Kobayashi, Kenji,Koyama, Emiko,Namatame, Kazuhiko,Kitaura, Toyokazu,Kono, Chihiro,Goto, Mariko,Obinata, Takanobu,Furukawa, Naomichi
, p. 3190 - 3195 (2007/10/03)
The remote Pummerer reaction of the mono-sulfoxide of p-bis(methylthio)-aromatic 1 is described. The reaction of 1 with (CF3CO)2O in CH2Cl2 gave a mixture of the corresponding mono-Pummerer product 2, the bis-Pummerer product 3, and the bis-sulfide 4 in an n:1:1 ratio (n ≥ 2). The 1:1 formation of 3 and 4 indicates an intermolecular interaction between sulfur atoms. The reaction with the deuterium-labeled 1-d3 showed that the formation of 2 occurs at the sulfenyl as well as sulfinyl groups in 1a-d3-1d-d3, in which the product ratio of 2-d3:2-d2 is in the range of 3.5-10. On the other hand, the Pummerer reaction of 1e-d3 occurred preferably at the sulfinyl group in a usual manner. The reaction of a 1:1 mixture of the bis-sulfide 4 and the bis-sulfoxide 5 with (CF3-CO)2O also gave 2, 3, and 4 in a ratio similar to that for the reaction of 1. The mechanism in the present remote Pummerer reactions is discussed in light of an intermolecular through-space interaction between the sulfonium and sulfenyl sulfur atoms, and a dithia dication dimer B and/or a bis(dithia dication) cyclic dimer C are proposed as intermediates.
Carbon Acidity. 66. Equilibrium Ion Pair Acidities of Substituted Diphenylmethanes in Cyclohexylamine
Streitwieser, Andrew Jr.,Vorpagel, Erich R.,Chen, Chia-Chung
, p. 6970 - 6975 (2007/10/02)
The pKCsCHA values are reported for a number of symmetrically meta- and para-substituted diphenylmethanes.The pKCsCHA values for the meta series (Me, 33.8; OMe, 32.7; F, 29.9; CF3, 28.9; Ph, 32.3; H, 33.4) give a normal Hammett plot with ρ = 9.69.The para series (Me, 35.1; OMe,37.6; Ph, 30.8; NMe2, 38.6; SPh, 28.8; CN, 23.0; SO2Me, 22.4) do not fit attempted correlations with ?, the Yukawa-Tsuno modifications, or dual substituent parameter approaches.Electron-donating groups are more anion destabilizing than in other reference systems. "Amphoteric" substituents, those that stabilize both anions and cations (phenyl, thio, etc.), cause special problems in generalized correlations.
