6746-94-7Relevant articles and documents
Evidence for Concert in the Thermal Unimolecular Vinylcyclopropane to Cyclopentene Sigmatropic 1,3-Shift
Gajewski, Joseph J.,Olson, Leif P.,Willcott, M. Robert
, p. 299 - 306 (1996)
Gas phase pyrolysis of cis-2,3-dideuterio-trans-(1'-tert-butyl-2'-(Z)-deuteriovinyl)cyclopropane at 290 deg C gives trans,trans-3,4,5-trideuterio-1-tert-butylcyclopentene as the major 1,3-shift product with greater than 90percent stereospecificity in an orbital symmetry "allowed" suprafacial-inversion sense after correction for the geometric isomerization of starting material and the other materials present.The isotopic substitution at the critical sites of rearrangement eliminates steric of electronic influences of substitutents on a biradical pathway as a source of the suprafacial- inversion stereochemistry observed with more highly substituted drivatives.The stereochemical results coupled with a normal deuterium kinetic isotope effect (kH/2kD=1.14 at 311.6 deg C) at the exo-methylene carbon are best interpreted in terms of a concerted pathway for rearrangement.A less likely alternative is a stereospecific disrotatory ring opening to a biradical followed by rate-determining closure to a five-membered ring.Accompanying the rearrangement is geometric isomerization of starting material resulting from C-1-C-2 bond fission which favors either the single methylene rotation or a double rotation by a factor of 10 over single rotation at the vinyl-bearing carbon.
Safe and environment-friendly preparation method of cyclopropyl acetylene
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Paragraph 0037-0070, (2020/08/22)
The invention relates to the field of medicine synthesis, and discloses a safe and environment-friendly preparation method of cyclopropylacetylene, which comprises the following steps: 1) performing chlorination reaction; 2) carrying out an ethynylation reaction; and 3) synthesizing cyclopropyl methyl ketone from the by-product E/Z-2, 5-dichloro-2-pentene. The process provided by the invention ishigh in chlorination yield; the chlorination reagent is triphosgene, the reaction condition is mild, and the safety is high. An organic solvent, inorganic base and a phase transfer catalyst system areadopted in the ethynylation reaction, and the yield is high; the high-flash-point organic solvent dilutes the reaction system, and the reaction is safe. E/Z-2-5-dichloro-2-pentene generated through the chlorination reaction is subjected to sulfuric acid dechlorination and cyclization and then converted into cyclopropyl methyl ketone, and application is achieved. Potassium chloride is treated as aby-product, and an organic solvent, water, organic alkali and a catalyst are used in chlorination reaction; an organic solvent and a phase transfer catalyst used in the ethynylation reaction can be recycled. The reaction is environment-friendly, only two potassium salt byproducts of potassium chloride and potassium sulfate are formed, and zero emission is basically realized.
Brand-new synthetic process route of cyclopropyl acetylene (by machine translation)
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Paragraph 0028-0032, (2020/05/30)
The process route of, is that the raw materials used by the two-step reaction, are easily available, the reaction conditions are mild, no three wastes are generated, the process route, is easy to operate, the yield is high, the yield is high, the, yield is high, and the industrial production, can be realized through the process route of the process route only through the two-step reaction, scheme of, the process, route shown, in the present invention. (by machine translation)
Palladium-Catalyzed Cascade Intramolecular Cyclization and Allylation of Enynoates with Allylic Alcohols
Qiu, Sheng-Qi,Ahmad, Tanveer,Xu, Yun-He,Loh, Teck-Peng
, p. 6729 - 6736 (2019/06/14)
A Pd(II)-catalyzed mild and highly regioselective 6-endo cyclization/allylation reaction of enynoates with simple allylic alcohols has been developed. Under mild reaction conditions, the vinyl palladium species generated in situ after cyclization could insert C-C double bond of allylic alcohol through cross-coupling reaction and lead to the formation of allyl pyrone via β-OH elimination. This cascade cross-coupling reaction represents a direct and atom economic methodology for the construction of novel allyl pyrones in moderate to good yields.
Method for preparing substituted alkynyl group-containing cyclopropyl compound
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Paragraph 0026; 0027, (2018/04/03)
The invention relates to the field of organic synthesis, and discloses a method for preparing a substituted alkynyl group-containing cyclopropyl compound. The method comprises the following steps: mixing and reacting a diolefin compound ii used as a starting material with a diazo compound iv in a solvent under the action of a catalyst to obtain a reaction solution containing a propyl compound iii;and adding the obtained reaction solution to acid water or hot water, performing washing, and adding an inorganic or organic alkali to adjust the pH value to 11-14 to prepare the substituted alkynylgroup-containing cyclopropyl compound. The method has the advantages of increase of the yield of the reaction, cheap and readily available industrial raw materials, reduction of by-products and reduction of environmental pollution.
Preparation method for compound containing alkynyl and cyclopropyl
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Paragraph 0024; 0025; 0026; 0027; 0028, (2018/03/07)
The invention relates to the field of organic synthesis, and discloses a preparation method for a compound containing alkynyl and cyclopropyl. The method comprises the following steps: a compound ii with alkyne and alkene is taken as a starting raw material, under effects of a catalyst, the compound ii with the alkyne and the alkene and a diazo substance iv are mixed and reacted in a solvent, andtherefore a reaction liquid containing a compound iii is obtained; and the obtained reaction liquid is added into acid water or hot water for washing, then an inorganic alkali or an organic alkali isadded to adjust the pH to 8-14, and therefore the compound I containing the alkynyl and the cyclopropyl is obtained. The method provided by the invention has the following beneficial effects: 1) the yield of the reaction is improved; 2) the industrialized raw materials used by the method are cheap and easy to obtain; and 3) by-products are reduced, and environmental pollution is reduced.
METHOD FOR THE MANUFACTURE OF EFAVIRENZ
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Page/Page column 23, (2018/09/19)
This invention relates to a method for the manufacture of optically pure (S)-6- chloro-(cyclopropylethynyl)-1,4-dihydro-4-(trifluoromethyl)-2H-3,1 -benzoxazin- 2-one. Specifically, this invention relates to a flow synthesis method for the manufacture of (S)-6-chloro-(cyclopropylethynyl)-1,4-dihydro-4- (trifluoromethyl)-2H-3,1 -benzoxazin-2-one.
Controlled photorelease of alkynoic acids and their decarboxylative deprotection for copper-catalyzed azide/alkyne cycloaddition
Vohradská, Nikoleta,Sánchez-Carnerero, Esther M.,Pastierik, Tomá?,Mazal, Ctibor,Klán, Petr
supporting information, p. 5558 - 5561 (2018/06/04)
A controlled photorelease of alkynoic acids from the meso-methyl BODIPY photoremovable protecting group facilitates their subsequent efficient decarboxylation to give terminal alkynes for a CuI-catalyzed azide/alkyne cycloaddition. The quantum efficiencies of the photochemical step and the kinetics of the click reaction step are reported.
A method for the preparation of cyclopropyl acetylene (by machine translation)
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Paragraph 0018; 0019; 0020; 0021; 0022; 0023, (2017/04/29)
The invention discloses a method for the preparation of cyclopropyl acetylene, the preparation method in order to cyclopropane ketone and phosphorus pentachloride as raw materials, in order to waste polyester material in the alcoholysis in the methanol solution of the obtained terephthalic acid armor alcohol ester and glycol as the reaction medium, in - 10 - 0 °C temperature stirring for 1 - 10 hours, then adding potassium hydroxide, stirring at the same temperature the reaction, gas chromatography tracking detection until a reaction is finished, filtering the solid, rectification cyclopropylacetylene product after the purification. In the present invention, waste polyester material in the alcoholysis in the methanol solution of the obtained terephthalic acid armor alcohol ester (DMT) and ethylene glycol (EG) as reaction medium, using a one-pot reaction technology for preparation of cyclopropyl acetylene, such that the process becomes simple, easy to operate, has reduced the three waste discharge, small pollution to the environment, and is a green clean integrated production technology, is suitable for the industrial production of a certain size. The method has not yet been reported, for the preparation of cyclopropyl acetylene provides a new way of thinking. (by machine translation)
Lanthanide-Catalyzed Reversible Alkynyl Exchange by Carbon–Carbon Single-Bond Cleavage Assisted by a Secondary Amino Group
Shao, Yinlin,Zhang, Fangjun,Zhang, Jie,Zhou, Xigeng
supporting information, p. 11485 - 11489 (2016/10/24)
Lanthanide-catalyzed alkynyl exchange through C?C single-bond cleavage assisted by a secondary amino group is reported. A lanthanide amido complex is proposed as a key intermediate, which undergoes unprecedented reversible β-alkynyl elimination followed by alkynyl exchange and imine reinsertion. The in situ homo- and cross-dimerization of the liberated alkyne can serve as an additional driving force to shift the metathesis equilibrium to completion. This reaction is formally complementary to conventional alkyne metathesis and allows the selective transformation of internal propargylamines into those bearing different substituents on the alkyne terminus in moderate to excellent yields under operationally simple reaction conditions.
