- Method for efficiently synthesizing pyridine chlorides
-
The invention discloses a method for efficiently synthesizing a pyridine chloride. The method comprises the following steps: introducing chlorine into methylpyridine in a solvent, and activating witha ligand catalyst; and after the activation is finished, separating and removing the solvent to obtain activated methylpyridine, carrying out a chlorine gas introduction reaction at a certain temperature, and after the reaction is finished, carrying out distillation separation to obtain 2,3-dichloro-5-trichloromethylpyridine. According to the process disclosed by the invention, methylpyridine is firstly activated by adopting an efficient ligand catalyst, then chlorine is introduced for chlorination, the chlorination process has high selectivity, the reaction condition is mild, the equipment operation is simple, few polychlorinated impurities are generated in the reaction process, and the process has high operability and economical efficiency.
- -
-
Paragraph 0025-0027; 0030-0032; 0035-0037; 0040-0042; 0045
(2020/06/09)
-
- A 2,3-chloro-5-chlorotrifluoromethylbenzene methylpyridinio synthetic method (by machine translation)
-
The invention relates to a 2,3 the [...] -5 the method for synthesizing methylpyridinio [...], which belongs to the field of chemical synthesis. Traditional production 2, the 3 [...] -5 the backward [...] methylpyridinio process, flow is long, the yield is low, a large amount of the three wastes, it is difficult to control. The present invention provides a mild reaction conditions, the high yield of 2,3 the [...] -5 the method for synthesizing methylpyridinio [...]. (by machine translation)
- -
-
Paragraph 0007
(2016/11/02)
-
- Rh/Pd catalysis with chiral and achiral ligands: Domino synthesis of aza-dihydrodibenzoxepines
-
A game of dominoes: A synthetic route to aza-dihydrodibenzoxepines is described, through the combination of a Rh-catalyzed arylation and a Pd-catalyzed C-O coupling in a single pot. For the first time, the ability to incorporate a chiral and an achiral ligand in a two-component, two-metal transformation is achieved, giving the products in moderate to good yields, with excellent enantioselectivities. Copyright
- Friedman, Adam A.,Panteleev, Jane,Tsoung, Jennifer,Huynh, Vaizanne,Lautens, Mark
-
supporting information
p. 9755 - 9758
(2013/09/23)
-
- CONVENIENT APPROACHES TO HETEROCYCLES VIA COPPER-CATALYSED ADDITIONS OF ORGANIC POLYHALIDES TO ACTIVATED OLEFINS
-
An efficient method for the synthesis of 2,3-dichloro-5-substituted (Cl, CF3, alkyl) pyridines 29 starting from the 1:1 adducts of the copper-catalysed addition of chloral or the corresponding 2,2-dichloroaldehydes to acrylonitrile is presented.Proper choice of experimental conditions allows the preparation of 29 in one-pot process.Similarly, the CuCl-catalysed reaction of methyl itaconate with several trichloromethyl compounds R-CCl3 gives 6-R-substituted 2-pyrone derivatives 40 via dehalogenation and subsequent thermal ring closure of the primary 1:1-adducts. The new electrophilic 2-pyrone 40b undergoes-cycloaddition reactions with inverse electron demand with a number of olefins and acetylenes, allowing thereby regioselective transfer of a trifluoromethyl group from a simple Freon derivative (1,1,1-trichloro-2,2,2-trifluoroethane) into more complex organic molecules.Finally, the 1:1-adduct of trichloroacetylchloride with methyl acrylate allows a very covenient synthesis of novel N-substituted derivatives 66 of pyroglutamic acid as well as of proline.
- Martin, Pierre,Steiner, Eginhard,Streith, Jacques,Winkler, Tammo,Bellus, Daniel
-
p. 4057 - 4078
(2007/10/02)
-
- Synthesis of Halogenated Pyridines via the CuCl-Catalyzed Addition of Polyhaloacetonitriles to Olefins
-
Halogenated acetonitriles add smoothly to acrolein, methacrolein, and methacrolein dimethyl acetal in the presence of a catalytic amount of CuCl and triphenylphosphine, tri-n-butylphosphine, or triethylamine to give halogenated difunctional adducts.The adducts have been cyclized in high yields under acidic conditions to halogenated pyridines.
- Pews, R. Garth,Lysenko, Zenon
-
p. 5115 - 5119
(2007/10/02)
-
- Process for the preparation of substituted pyridines
-
Substituted pyridines are prepared by the base and transition metal catalyzed ring closure of substituted 5-oxo-pentane-1-nitriles.
- -
-
-
- Process for the production of chloropyridines substituted by methyl, trichloromethyl or trifluoromethyl groups
-
Chloropyridines of the formula STR1 wherein either R is chlorine and R' is methyl or trifluoromethyl, or R is methyl, trichloromethyl or trifluoromethyl and R' is chlorine, or R and R' are methyl, can be obtained by a novel, simple process by the addition of trichloroacetaldehyde to methacrylonitrile or α-trifluoromethacrylonitrile, 2,2-dichloropropionaldehyde, pentachloropropionaldehyde or 2,2-dichloro-3,3,3-trifluoropropionaldehyde to acrylonitrile, or 2,2-dichloropropionaldehyde to methacrylonitrile, in the presence of a catalyst, in particular copper powder or copper(I) chloride, and cyclizing the open-chain intermediate obtained. The chloropyridines of the formula (I) are known per se and are suitable for the production of different compounds, in particular of insecticides and herbicides.
- -
-
-
