63318-20-7Relevant articles and documents
Practical and Selective sp3 C?H Bond Chlorination via Aminium Radicals
McMillan, Alastair J.,Sieńkowska, Martyna,Di Lorenzo, Piero,Gransbury, Gemma K.,Chilton, Nicholas F.,Salamone, Michela,Ruffoni, Alessandro,Bietti, Massimo,Leonori, Daniele
supporting information, p. 7132 - 7139 (2021/03/03)
The introduction of chlorine atoms into organic molecules is fundamental to the manufacture of industrial chemicals, the elaboration of advanced synthetic intermediates and also the fine-tuning of physicochemical and biological properties of drugs, agrochemicals and polymers. We report here a general and practical photochemical strategy enabling the site-selective chlorination of sp3 C?H bonds. This process exploits the ability of protonated N-chloroamines to serve as aminium radical precursors and also radical chlorinating agents. Upon photochemical initiation, an efficient radical-chain propagation is established allowing the functionalization of a broad range of substrates due to the large number of compatible functionalities. The ability to synergistically maximize both polar and steric effects in the H-atom transfer transition state through appropriate selection of the aminium radical has provided the highest known selectivity in radical sp3 C?H chlorination.
MECHANISMS OF FREE-RADICAL REACTIONS. XXIV. QUANTITATIVE DESCRIPTION OF THE POLAR EFFECTS OF SUBSTITUENTS ON THE KINETICS OF THE FREE-RADICAL CHLORINATION OF ALIPHATIC COMPOUNDS BY N-CHLOROPIPERIDINE
Dneprovskii, A. S.,Mil'tsov, S. A.,Arbuzov, P. V.
, p. 1826 - 1835 (2007/10/02)
The free-radical chlorination of 1-substituted alkanes with electron-withdrawing substituents by N-chloropiperidine in trifluoroacetic acid was studied by the method of competing reactions, and the relative rate constants were obtained for all positions of the substrates.The data on the position selectivity can be described satisfactorily by means of an electrostatic model of the polar effect of the substituent, calculated according to the Kirkwood-Westheimer equation.The obtained characteristics of the electrostatic effect can be successfully applied to calculation of the substrate selectivity and the intermolecular relative rate constants for all the positions, beginning with the third.The Taft equation is unsuitable for description of the effect of substituents on the reaction rate.
MECHANISMS OF FREE-RADICAL REACTIONS. XIV. SELECTIVITY OF FREE-RADICAL CHLORINATION OF VALERIC ACID DERIVATIVES WITH ARYLCHLOROIODONIUM CHLORIDES
Dneprovskii, A. S.,Krainyuchenko, I. V.
, p. 324 - 328 (2007/10/02)
The free-radical chlorination of C4H9Y compounds with arylchloroiodonium chlorides was investigated.The reaction of the secondary C-H bonds increases as they become further from the electronegative substituent.The reaction parameters were calculated from the ratio of the β- and γ-monochlorides by means of the Taft equation.The absolute value of ρ increases with the introduction of electronwithdrawing substituents into the arylchloroiodonium chloride molecule.
Chlorination of Carboxylic Acid Derivatives. VIII. Liquid Phase Chlorination of the Aliphatic C5-Carboxylic Acids and Their Chlorides, Methyl Esters and Chloromethyl Esters with Chlorine
Kornonen, Ilpo O. O.
, p. 467 - 474 (2007/10/02)
The chlorination of pentanoic, 3-methylbutanoic, 2-methylbutanoic and 2,2-dimethylpropanoic acids and their derivatives with chlorine in the liquid phase have been investigated.The monochloro products formed were determined by gas-liquid chromatography (GLC) and gas-liquid chromatography-mass spectrometry (GLC-MS) as their esters through the comparison with authentic samples.The deactivation of position 2 decreases in the order COCl > CO2H > CO2CH2Cl > CO2CH3, the effect of the COCl-group in pentanoic acid derivatives being 4.3 times stronger than that of the CO2CH3-group.The deactivation is smallest in 2-methylbutanoic acid derivatives owing to the electron-donating methyl group.The EI mass spectra of the methyl and chloromethyl esters have been studied in detail.
Chlorination of Esters. I. Chlorination of Methyl Esters of Propanoic, Butanoic, Pentanoic and Hexanoic Acids. The Isomer Distribution of Monochloro Esters Formed
Korhonen, Ilpo O.O.,Korvola, Jorma N.J.
, p. 139 - 142 (2007/10/02)
The chlorination of methyl ester with chlorine in the liquid and vapor phase and with sulfuryl chloride in the liquid phase has been investigated.The chlorination yields all possible monochloro esters isomers with the 2-chloro isomer in the smallest amount.The products were identified by NMR and mass spectrometry.The isomer distribution and mass spectra of products were studied in detail.
