957188-75-9Relevant articles and documents
Benchtop-Stabssle Hypervalent Bromine(III) Compounds: Versatile Strategy and Platform for Air- And Moisture-Stable λ3-Bromanes
Miyamoto, Kazunori,Saito, Motomichi,Tsuji, Shunsuke,Takagi, Taisei,Shiro, Motoo,Uchiyama, Masanobu,Ochiai, Masahito
supporting information, p. 9327 - 9331 (2021/07/01)
We present the first synthesis of air/moisture-stable λ3-bromanes (9and10) by using a cyclic 1,2-benzbromoxol-3-one (BBX) strategy. X-ray crystallography and NMR and IR spectroscopy ofN-triflylimino-λ3-bromane (12) revealed that the bromine(III) center is effectively stabilized by intramolecular R-Br-O hypervalent bonding. This strategy enables the synthesis of a variety of air-, moisture-, and benchtop-stable Br-hydroxy, -acetoxy, -alkynyl, -aryl, and bis[(trifluoromethyl)sulfonyl]methylide λ3-bromane derivatives.
Synthesis and structure of hypervalent diacetoxybromobenzene and aziridination of olefins with imino-λ3-bromane generated in situ under metal-free conditions
Hoque, Md. Mahbubul,Miyamoto, Kazunori,Tada, Norihiro,Shiro, Motoo,Ochiai, Masahito
, p. 5428 - 5431 (2011/11/30)
Ligand exchange of p-CF3C6H4BrF 2 with acetoxy groups using AcOH and Ac2O affords (diacetoxybromo)benzene in a high yield, which undergoes aziridination of alkenes in the presence of TfNH2
Highly regioselective amination of unactivated alkanes by hypervalent sulfonylimino-δ3-bromane
Ochiai, Masahito,Miyamoto, Kazunori,Kaneaki, Takao,Hayashi, Satoko,Nakanishi, Waro
scheme or table, p. 448 - 451 (2011/10/31)
Amination of alkanes has generally required metal catalysts and/or high temperatures. Here we report that simple exposure of a broad range of alkanes to N-triflylimino-δ3-bromane 1 at ambient temperature results in C-H insertion of the nitrogen functionality to afford triflyl-substituted amines in moderate to high yields. Marked selectivity for tertiary over secondary C-H bonds was observed; primary (methyl) C-H bonds were inert. Addition of hexafluoroisopropanol to inhibit decomposition of 1 dramatically improved the C-H amination efficiencies. Second-order kinetics, activation parameters (negative activation entropy), deuterium isotope effects, and theoretical calculations suggest a concerted asynchronous bimolecular transition state for the metal-free C-H amination event.
Imination of sulfides and sulfoxides with sulfonylimino- λ3-bromane under mild, metal-free conditions
Ochiai, Masahito,Naito, Masao,Miyamoto, Kazunori,Hayashi, Satoko,Nakanishi, Waro
scheme or table, p. 8713 - 8718 (2010/10/19)
Exposure of sulfides and sulfoxides to trifluoromethanesulfonylimino(aryl)- λ3-bromane in dichloromethane at 0°C results in a facile transfer of the sulfonylimino group to sulfur atoms and affords N-triflylsulfilimines and -sulfoximines in high yields under transition-metal-free conditions. Imination of (R)-methyl p-tolyl sulfoxide proceeded with predominant retention of configuration at the stereogenic sulfur center. The Hammett plot afforded ρ values of -0.58 for para-substituted thioanisoles and -0.49 for their equivalent sulfoxides, which suggests a buildup of positive charge on the sulfur atoms of sulfides and sulfoxides in the transition state. Calculations suggest a bimolecular nucleophilic-substitution mechanism on the negatively charged nitrogen atom of the sulfonylimino- λ3-bromane, which involves the attack of a sulfide from the opposite side to bromine(III).
Direct transfer of the sulfonylimino group of imino-λ3- bromane to N-heterocycles and trialkylamines: Synthesis of N-iminoammonium ylides under metal-free conditions
Ochiai, Masahito,Kawano, Yufuko,Kaneaki, Takao,Tada, Norihiro,Miyamoto, Kazunori
body text, p. 281 - 284 (2009/08/08)
(Chemical Equation Presented) Exposure of N-heterocycles and aliphatic trialkylamines to trifluoromethanesulfonylimino-λ3-bromane at room temperature results in direct transfer of the sulfonylimino group to the nitrogen atoms and affords a vari
A new type of imido group donor: Synthesis and characterization of sulfonylimino-Δ3-bromane that acts as a nitrenoid in the aziridination of olefins at room temperature under metal-free conditions
Ochiai, Masahito,Kaneaki, Takao,Tada, Norihiro,Miyamoto, Kazunori,Chuman, Hiroshi,Shiro, Motoo,Hayashi, Satoko,Nakanishi, Waro
, p. 12938 - 12939 (2008/09/16)
A stable sulfonylimino-λ3-bromane, CF3SO2N--Br+C6H4-p-CF3, has been synthesized and structurally characterized for the first time. X-ray crystallographic analyses indi
