- Isomerization and decomposition of chloromethylacetylene
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The isomerization and thermal decomposition of chloromethylacetylene (CMA) has been studied with two shock tube techniques. The first experiment (Jerusalem) utilizes single-pulse shock tube methods to measure the isomerization rate of CMA to chloroallene. In addition, equilibrium constants can be estimated at ~1200 K. The second experiment (Argonne) monitors Cl-atom formation at temperatures above ~1150 K. Absolute yield measurements have been performed over the 1200-1700 K range and indicate that two decomposition channels contribute to CMA destruction, namely, Cl fission and HCl elimination. The results show that the branching fraction between processes is temperature dependent. Therefore, direct Cl-atom fission is accompanied by molecular elimination, undoubtedly giving HCl and one or more isomers of C3H2. MP2 6-31G(d,p) ab initio electronic structure calculations have been used to determine vibration frequencies and moments of inertia for three C3H3Cl isomers. Using these quantities, the experimental equilibrium constants required that ΔH00(CH2Cl-C≡CH ? CHCl=C=CH2) = -0.24 kcal mole-1. A potential energy surface pertinent to the present system has been constructed, and RRKM calculations have been carried out in order to explain the isomerization rates. The isomerization data can be explained with E0 = 52.3 kcal mole-1 and 〈ΔEdown〉 = 225 cm-1. Subsequent semi-empirical Troe and RRKM-Gorin modeling of the Cl atom rate data require E0 = (67.5 ± 0.5) kcal mole-1 with a (ΔEdown) = (365 ± 90) cm-1. This suggests a heat of formation for propargyl radicals of (79.0 ± 2 5) kcal mole-1.
- Kumaran, Soundararajan S.,Lim, Kee P.,Michael, Joe V.,Tilson, Jeffrey L.,Suslensky, Aya,Lifshitz, Assa
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- Reaction of tellurium tetrachloride with propargyl halides
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The reaction of tellurium tetrachloride with propargyl bromide in boiling benzene regio- and stereoselectively afforded bis[(Z)-3-bromo-2-chloroprop-1-en-1-yl]tellurium dichloride which was readily reduced to bis[(Z)-3-bromo-2-chloroprop-1-en-1-yl] telluride. Propargyl chloride reacted with tellurium tetrachloride preliminarily stored for several months (and containing decomposition products) to give a mixture of bis[(Z)-2,3-dichloroprop-1-en-1-yl]tellurium dichloride and regioisomeric [(Z)-1,3-dichloroprop-1-en-2-yl]- [(Z)-2,3-dichloroprop-1-en-1-yl]tellurium dichloride at a ratio of 3: 2, whereas the latter was formed as the sole product in the reaction with freshly prepared tellurium tetrachloride. Reduction of the regioisomer mixture produced the corresponding tellurides. The structure of the isolated compounds was confirmed by 1H, 13C, and 125Te NMR spectra.
- Martynov,Makhaeva,Larina,Amosova
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- A mild method for the replacement of a hydroxyl group by halogen: 3. the dichotomous behavior of α-haloenamines towards allylic and propargylic alcohols
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A study of the deoxyhalogenation of allylic and propargylic alcohols with tetramethyl-α-halo-enamines is reported. Primary allylic and primary and secondary propargylic alcohols gave the corresponding halides in high yields. Secondary allylic and propargylic alcohols yielded the corresponding secondary halides but the reaction also produced some rearranged primary halides (I > Br > Cl). The reactions with tertiary allylic and tertiary propargylic alcohols gave several products and was therefore of little synthetic value. However, the addition of triethylamine to the reaction mixture or the use of lithium alkoxide instead of alcohol brought about a major change of the course of the reaction which led to amides carrying an allyl or an allenyl group at C2. This was shown to result from a Claisen-Eschenmoser rearrangement of an intermediate α-allyloxy- or propargyloxy-enamine.
- Munyemana, Fran?ois,Patiny, Luc,Ghosez, Léon
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- Novel synthesis method of propyzamide
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The invention relates to the technical field of pesticide synthesis, and provides a novel synthesis method of propyzamide, which comprises the following steps: S1, adding 3, 5-dichlorobenzoyl chloride, 3-amino-3-methyl-1-butyne and a solvent into a reaction kettle, and starting stirring; S2, heating to 20 DEG C, adding an acid-binding agent and a compound catalyst into the reaction kettle, and reacting for 4-6 hours; S3, after the reaction is finished, adding water, adding dichloroethane, and layering; S4, adding the layered organic phase into a sulfuric acid solution with the concentration of 2.0 mol/L-3. 0mol/L, regulating the pH value to 6-7, cooling to 5 DEG C, stirring for 2 hours, and centrifugally filtering to obtain the propyzamide product. Through the technical scheme, the problems of long reaction time and poor product quality in the prior art are solved.
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Paragraph 0020-0021; 0022-0023; 0024-0025; 0026-0031
(2021/04/17)
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- METHOD OF CONVERTING ALCOHOL TO HALIDE
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The present invention relates to a method of converting an alcohol into a corresponding halide. This method comprises reacting the alcohol with an optionally substituted aromatic carboxylic acid halide in presence of an N-substituted formamide to replace a hydroxyl group of the alcohol by a halogen atom. The present invention also relates to a method of converting an alcohol into a corresponding substitution product. The second method comprises: (a) performing the method of the invention of converting an alcohol into the corresponding halide; and (b) reacting the corresponding halide with a nucleophile to convert the halide into the nucleophilic substitution product.
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Page/Page column 53; 113; 114
(2017/01/02)
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- PROCESS FOR MANUFACTURING 4-PROPARGYLATED AMINO-BENZOXAZINONES
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The present invention relates to a process for manufacturing 4-propargylated amino- benzoxazinones of formula (I), comprising the following steps: step a) preparing propargyl chloride by reacting propargyl alcohol with thionyl chloride optionally in the presence of a catalyst; and step b) reacting the propargyl chloride prepared in step (a) with a NH-benzoxazinone of formula (II); wherein the variables are defined according to the description.
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Page/Page column 18
(2015/01/07)
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- Copper(I)-catalyzed regio- and chemoselective single and double addition of nucleophilic silicon to propargylic chlorides and phosphates
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Copper(I)-catalyzed propargylic substitution of linear precursors with (Me2PhSi)2Zn predominantly yields the γ isomer independent of the propargylic leaving group. The thus formed allenylic silane reacts regioselectively with another equivalent of (Me2PhSi) 2Zn, yielding a bifunctional building block with allylic and vinylic silicon groups. The reaction rates of both steps are well-balanced for chloride (γ:α ≥ 99:1) where the propargylic displacement occurs quantitatively prior to the addition step. Substitutions of α-branched propargylic phosphates are also reported.
- Hazra, Chinmoy K.,Oestreich, Martin
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supporting information; experimental part
p. 4010 - 4013
(2012/10/08)
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- Copper(I)-catalyzed regioselective propargylic substitution involving Si-B bond activation
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The silicon nucleophile generated by copper(I)-catalyzed Si-B bond activation allows several γ-selective propargylic substitutions. The regioselectivity (γ:α ratio) is strongly dependent on the propargylic leaving group. Chloride is superior to oxygen leaving groups in linear substrates (γ:α > 99:1), and it is only the phosphate group that also shows promising regiocontrol (γ:α = 90:10). That leaving group produces superb γ-selectivity (γ:α > 99:1) in α-branched propargylic systems, and enantioenriched substrates react with excellent central-to-axial chirality transfer.
- Vyas, Devendra J.,Hazra, Chinmoy K.,Oestreich, Martin
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supporting information; experimental part
p. 4462 - 4465
(2011/10/08)
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- Reaction of N,N-dichloroarenesulfonamides with propargyl alcohol
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The reaction of N,N-dichloroarenesulfonamides with propargyl alcohol gives 3-hydroxy-2,2-dichloro-1,1-di(N-arenesulfonamido)propanes and N-(3-hydroxy-2,2-dichloropropylidene)arenesulfonamides. The latter were obtained due to the transformation of intermediate products, N-chloro-N-(3-hydroxy-2-chloro1-propenyl)arenesulfonamides, by the 1,3-migration of the halogen atom. The addition of arenesulfonamides formed in the reaction to N-(3-hydroxy-2,2-dichloropropylidene)arenesulfonamides results in the formation of 3-hydroxy-2,2-dichloro-1,1-di(N-arenesulfonamido)propanes.
- Drozdova,Kozyreva,Mirskova
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p. 243 - 245
(2007/10/03)
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- SYNTHESIS OF ALKYL HALIDES UNDER NEUTRAL CONDITIONS
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Primary and secondary alcohols are efficiently converted to the corresponding alkyl halides under neutral conditions.
- Munyemana, Francois,Frisque-Hesbain, Anne-Marie,Devos, Alain,Ghosez, Leon
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p. 3077 - 3080
(2007/10/02)
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- SYNTHESIS OF BROMOALLENE UNDER CONDITIONS OF PHASE-TRANSFER CATALYSIS
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A new method was developed for the production of bromoallene by the dehydrobromination of 1,2,3-tribromopropane under the conditions of phase-transfer catalysis.It was shown that the bromoallene is produced as a result of the isomerization of the initially formed propargyl bromide.During the dehydrohalogenation of 2-bromo-3-chloro-1-propene, bromoallene, i.e.; the product from rearrangement with participation of the bromine atom, is formed in addition to propargyl chloride and chloroallene.
- Kurginyan, K. A.,Arakelova, S. V.,Kalaidzhyan, A. E.
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p. 2127 - 2130
(2007/10/02)
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- Carbon-Halogen Bonding Studies. Halogen Redistribution Reactions between Alkyl or Acetyl Halides and Tri-n-butyltin Halides
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The equilibrium positions have been determined for the halogen redistribution reactions of tri-n-butyltin halides with a variety of structurally different types of alkyl halides and with acetyl halides.These have been related through the reaction ΔGo values to carbon-halogen bond dissociation energy differences.It is suggested that the trends observed in the latter may provide evidence for the existence of a small steric bond weakening effect in the order C-I > C-Br > C-Cl bonds on going from methyl to primary, secondary, and tertiary alkyl halides.On the other hand, with the 2,3-? bond containing allyl, benzyl, and propargyl halides , α-haloacetones, and haloacetonitriles, there may be some type of electronic carbon-halogen bond strengthening effect which lies in order C-I > C-Br > C-Cl.Finally, for the acetyl halides, the data are in agreement with increases in bond strengths resulting from ? contributions being in the order C-Cl > C-Br > C-I.
- Friedrich, Edwin C.,Abma, Charles B.
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p. 1367 - 1371
(2007/10/02)
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- Trimethylhalosilane elimination from trimethylsilylsubstituted gem-dihalocyclopropanes
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The aluminum halide-catalyzed elimination of trimethylhalosilane from 1,1-dihalo-2-(trimethylsilyl)cyclopropanes (XCl and Br) resulted in the formation of propargyl halides, HCCCH2X. Reaction of 1,1-dichloro-2,2-dimethyl-3-(trimethylsilyl) cyclopropane with sodium ethoxide in ethanol also resulted in elimination of trimethylchlorosilane; the organic product was 3-ethoxy-3-methyl-1-butyne, HCCCMe2OEt, and a mechanism involving β-elimination of trimethylchlorosilane to give 1-chloro-3,3-dimethylcyclopropene and reaction of the latter to produce the acetylenic ether is suggested.
- Seyferth, Dietmar,Jula, Theodore F.
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p. 109 - 114
(2007/10/05)
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