66898-13-3Relevant academic research and scientific papers
Alkylation of Sulfonamides with Trichloroacetimidates under Thermal Conditions
Wallach, Daniel R.,Chisholm, John D.
, p. 8035 - 8042 (2016/09/12)
An intermolecular alkylation of sulfonamides with trichloroacetimidates is reported. This transformation does not require an exogenous acid, base, or transition metal catalyst; instead the addition occurs in refluxing toluene without additives. The sulfonamide alkylation partner appears to be only limited by sterics, with unsubstituted sulfonamides providing better yields than more encumbered N-alkyl sulfonamides. The trichloroacetimidate alkylating agent must be a stable cation precursor for the substitution reaction to proceed under these conditions.
Nonheme iron-mediated amination of C(sp3)-H bonds. Quinquepyridine-supported iron-imide/nitrene intermediates by experimental studies and DFT calculations
Liu, Yungen,Guan, Xiangguo,Wong, Ella Lai-Ming,Liu, Peng,Huang, Jie-Sheng,Che, Chi-Ming
supporting information, p. 7194 - 7204 (2013/06/27)
The 7-coordinate complex [Fe(qpy)(MeCN)2](ClO4) 2 (1, qpy = 2,2′:6′,2″:6″, 2′′′:6′′′,2′′′′- quinquepyridine) is a highly active nonheme iron catalyst for intra- and intermolecular amination of C(sp3)-H bonds. This complex effectively catalyzes the amination of limiting amounts of not only benzylic and allylic C(sp3)-H bonds of hydrocarbons but also the C(sp3)-H bonds of cyclic alkanes and cycloalkane/linear alkane moieties in sulfamate esters, such as those derived from menthane and steroids cholane and androstane, using PhI=NR or "PhI(OAc)2 + H2NR" [R = Ts (p-toluenesulfonyl), Ns (p-nitrobenzenesulfonyl)] as nitrogen source, with the amination products isolated in up to 93% yield. Iron imide/nitrene intermediates [Fe(qpy)(NR)(X)]n+ (CX, X = NR, solvent, or anion) are proposed in these amination reactions on the basis of experimental studies including ESI-MS analysis, crossover experiments, Hammett plots, and correlation with C-H bond dissociation energies and with support by DFT calculations. Species consistent with the formulations of [Fe(qpy)(NTs)2] 2+ (CNTs) and [Fe(qpy)(NTs)]2+ (C) were detected by high-resolution ESI-MS analysis of the reaction mixture of 1 with PhI=NTs (4 equiv). DFT calculations revealed that the reaction barriers for H-atom abstraction of cyclohexane by the ground state of 7-coordinate C NTs and ground state of C are 15.3 and 14.2 kcal/mol, respectively, in line with the observed high activity of 1 in catalyzing the C-H amination of alkanes under mild conditions.
Efficient intermolecular iron-catalyzed amidation of C-H bonds in the presence of n-bromosuccinimide
Wang, Zhe,Zhang, Yongming,Fu, Hua,Jiang, Yuyang,Zhao, Yufen
supporting information; experimental part, p. 1863 - 1866 (2009/04/12)
We have developed an efficient, inexpensive, and air-stable catalyst/oxidant (FeCI2/NBS) system that could efficiently promote amidation of benzylic sp3 C-H bonds in ethyl acetate under mild conditions.
Imido transfer from bis(imido)ruthenium(VI) porphyrins to hydrocarbons: Effect of imido substituents, C-H bond dissociation energies, and Ru VI/V reduction potentials
Leung, Sarana Ka-Yan,Tsui, Wai-Man,Huang, Jie-Sheng,Che, Chi-Ming,Liang, Jiang-Lin,Zhu, Nianyong
, p. 16629 - 16640 (2007/10/03)
[RuVI(TMP)(NSO2R)2] (SO2R = Ms, Ts, Bs, Cs, Ns; R = p-C6H4OMe, p-C6H 4Me, C6H5, p-C6H4-Cl, p-C6H4NO2, respectively) and [Ru VI(Por)(NTs)2] (Por = 2,6-Cl2TPP, F 20-TPP) were prepared by the reactions of [RuII(Por)(CO)] with Phl=NSO2R in CH2Cl2. These complexes exhibit reversible RuVI/V couple with E1/2 = -0.41 to -0.12 V vs Cp2Fe+/10 and undergo imido transfer reactions with styrenes, norbornene, cis-cyclooctene, indene, ethylbenzenes, cumene, 9,10-dihydroanthracene, xanthene, cyclohexene, toluene, and tetrahydrofuran to afford aziridines or amides in up to 85% yields. The second-order rate constants (k2) of the aziridination/amidation reactions at 298 K were determined to be (2.6 ± 0.1) × 10-5 to 14.4 ± 0.6 dm3 mol-1 s-1, which generally increase with increasing RuVI/V reduction potential of the imido complexes and decreasing C-H bond dissociation energy (BDE) of the hydrocarbons. A linear correlation was observed between log K (K is the k2 value divided by the number of reactive hydrogens) and BDE and between log k2 and E1/2(RuVI/V); the linearity in the former case supports a H-atom abstraction mechanism. The amidation by [RuVI(TMP)(NNs) 2] reverses the thermodynamic reactivity order cumene > ethylbenzene/toluene, with K(3° C-H)/K(2° C-H) = 0.2 and K(3° C-H)/K(1° C-H) = 0.8.
