- Preparation method of dichloroalkane
-
The invention discloses a preparation method of dichloroalkane, which comprises the following steps: mixing diol, a catalyst and a solvent, stirring and heating the components, introducing HCl gas into the mixture, and carrying out reflux reaction for 3-5 hours; and after the reaction is finished, treating the reaction solution to obtain dichloroalkane. According to the preparation method providedby the invention, the catalyst ammonium chloride is added, so that the reaction speed is obviously increased, and side reactions are reduced. In the invention, a large amount of solvent water is added in the reaction process, so that on one hand, the formation of monochloro ether by-products can be effectively inhibited, a water phase can be directly and repeatedly used, and basically no sewage is discharged; besides, by using the oil-water separator, the dichloroalkane product can be effectively separated, the product purity is high, and the yield is high.
- -
-
Paragraph 0021
(2021/02/10)
-
- Practical and Selective sp3 C?H Bond Chlorination via Aminium Radicals
-
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.
- 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)
-
- Site-Selective Aliphatic C-H Chlorination Using N-Chloroamides Enables a Synthesis of Chlorolissoclimide
-
Methods for the practical, intermolecular functionalization of aliphatic C-H bonds remain a paramount goal of organic synthesis. Free radical alkane chlorination is an important industrial process for the production of small molecule chloroalkanes from simple hydrocarbons, yet applications to fine chemical synthesis are rare. Herein, we report a site-selective chlorination of aliphatic C-H bonds using readily available N-chloroamides and apply this transformation to a synthesis of chlorolissoclimide, a potently cytotoxic labdane diterpenoid. These reactions deliver alkyl chlorides in useful chemical yields with substrate as the limiting reagent. Notably, this approach tolerates substrate unsaturation that normally poses major challenges in chemoselective, aliphatic C-H functionalization. The sterically and electronically dictated site selectivities of the C-H chlorination are among the most selective alkane functionalizations known, providing a unique tool for chemical synthesis. The short synthesis of chlorolissoclimide features a high yielding, gram-scale radical C-H chlorination of sclareolide and a three-step/two-pot process for the introduction of the β-hydroxysuccinimide that is salient to all the lissoclimides and haterumaimides. Preliminary assays indicate that chlorolissoclimide and analogues are moderately active against aggressive melanoma and prostate cancer cell lines.
- Quinn, Ryan K.,K?nst, Zef A.,Michalak, Sharon E.,Schmidt, Yvonne,Szklarski, Anne R.,Flores, Alex R.,Nam, Sangkil,Horne, David A.,Vanderwal, Christopher D.,Alexanian, Erik J.
-
supporting information
p. 696 - 702
(2016/02/03)
-
- Is bond stretch isomerism in mononuclear transition metal complexes a real issue? The misleading case of the MoCl5/tetrahydropyran reaction system
-
Distinct batches of orange (1a-e) and green crystals (2a-e) were isolated from the reactions of MoCl5 with tetrahydropyran (thp), respectively at room temperature (in CH2Cl2) and at ca. 80°C (in ClCH2CH2Cl). Crystals 2a-e are isomorphous to 1a-e and the IR spectra are almost superimposable. 1a-e were identified by X-ray studies as cis-MoCl4(thp)2, in agreement with previous findings. Careful refinement of the X-ray data of 2a-e by modeling one position as disordered between chlorine (minor component) and oxygen (major component) led to the conclusion that 2a-e consisted of a mixture of cis-MoCl4(thp)2 and mer-MoOCl3(thp)2, the latter being largely prevalent.
- Di Nicola, Francesco Paolo,Lanzi, Massimiliano,Marchetti, Fabio,Pampaloni, Guido,Zacchini, Stefano
-
p. 12653 - 12659
(2015/07/15)
-
- Solid-state chlorodecarboxylation of mono- and dicarboxylic acids with the Pb(OAc)4-MCl system
-
Solid state reactions of acids RCOOH (R = n-C7H15, BuC(Et)H, n-C9H19, PhCH2, PhCH 2CH2, H2C=CH(CH2)8, or MeOOC(CH2)3) with Pb(OAc)4 combined with KCl, NaCl, CdCl2, or NH4Cl in the absence of a solvent and without mechanical activation afford chlorohydrocarbons RCl. The corresponding reactions of acids HOOC(CH2)nCOOH (n = 3-6) give dichloroalkanes Cl(CH2)nCl and γ-butyrolactone (n = 3).
- Nikishin,Sokova,Chizhov,Makhaev,Kapustina
-
p. 2200 - 2204
(2007/10/03)
-
- 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
-
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.
- Dneprovskii, A. S.,Mil'tsov, S. A.,Arbuzov, P. V.
-
p. 1826 - 1835
(2007/10/02)
-
- THE LONG-RANGE ACTION OF THE POLAR EFFECT OF SUBSTITUENTS ON THE ABSTRACTION OF HYDROGEN IN FREE-RADICAL CHLORINATION PROCESSES
-
The free-radical chlorination of 1-chloroalkanes between C3 and C6 at 263 deg K was studied under conditions with wide variation in the concentrations of the substrates in benzene.By analysis of the products from chlorination of the pure substrates it was shown that the deactivating effect of the polar substituent does not extend beyond the third carbon atom and is mainly determined by the inductive effect.In the transition to an aromatic solvent the deactivating effect on the substituent extends to the fourth carbon atom.The results are substantiated in terms of a contribution from dipole-dipole interaction between the substituent and the polar form of the transition state to the polar effect of the substituents.
- Aver'yanov, V. A.,Ruban, S. G.,Klykova, M. B.,Golubev, V. E.
-
p. 435 - 439
(2007/10/02)
-
- MECHANISMS OF FREE-RADICAL REACTIONS. XIX. SELECTIVITY OF THE FREE-RADICAL CHLORINATION OF 1-CHLOROALKANES BY N-CHLOROPIPERIDINE
-
The free-radical chlorination of 1-chloroalkanes ClH2l+1Cl (l = 4-7) by N-chloropiperidine was studied by the method of competing reactions, and the relative constants for all the positions of the investigated substrates were determined.The chlorination is a highly electrophilic process, and the effect of the substituents is transmitted through at least six C-C bonds.The results can be described satisfactorily by means of an electrostatic model of the polar effect of the substituents according to the Kirkwood-Westheimer equation.At the same time an attempt to describe the obtained data by means of the Taft equation led to unsatisfactory results.
- Dneprovskii, A. S.,Mil'tsov, S. A.
-
p. 265 - 269
(2007/10/02)
-
- Metal-assisted Reactions. Part 17. Ring-opening and Dimerization of Cyclic Ethers by Titanium Halides
-
Reaction of TiCl4 or TiBr4 with a variety of cyclic ethers gives, predominantly, products resulting from simple ring-opening or from ring-opening with simultaneous condensation to dimeric species.The variations in yields of these two kinds of products might be correlated qualitatively with an initial formation of the complex TiX4*2E (X = Cl or Br; E = cyclic ether) in which the ethers were held in a cis or trans relationship.Although such a correlation might suggest that TiCl4 but not TiBr4 exerts a template effect on the condensation, stereochemical considerations of the reaction products indicate otherwise.TiCl3 and VCl3 do not give similar results and TiF4 gives no reaction.
- Delaney, Paul A.,Johnstone, Robert A. W.,Entwistle, Ian D.
-
p. 1855 - 1860
(2007/10/02)
-
- Cyclodehydration and Chlorination of Simple Diols with Triphenylphosphine and tert-Butyl Hypochlorite
-
The reagent triphenylphosphine-tert-butyl hypochlorite converts 1,4-diols into the corresponding tetrahydrofurans and 1,2-diols into a mixture of the regioisomeric chlorohydrins and the epoxides at -78 deg C followed by warming to ambient temperature (ca. 30 deg C).Symmetrical diols give largely chlorohydrins and dichlorides.
- Barry, Carey N.,Evans, Slayton A.
-
p. 2825 - 2828
(2007/10/02)
-
- SYNTHESIS OF HIGHER ACETYLENIC ALCOHOLS
-
The alkylation of 1-alkynes in various solvents was investigated, and the optimum conditions for the production of acetylenic alcohols were obtained.
- Kovalev, B. G.,Matveeva, E. D.,Stan, V. V.,Vovk, G. A.,Yudin, L. G.,Kost, A. N.
-
p. 1728 - 1733
(2007/10/02)
-