42201-71-8Relevant academic research and scientific papers
Monosubstituted 3,3-Difluorocyclopropenes as Bench-Stable Reagents: Scope and Limitations
Nosik, Pavel S.,Pashko, Mykola O.,Poturai, Andrii S.,Kvasha, Denys A.,Pashenko, Alexander E.,Rozhenko, Alexander B.,Suikov, Sergiy,Volochnyuk, Dmitriy M.,Ryabukhin, Sergey V.,Yagupolskii, Yurii L.
, p. 6604 - 6615 (2021/12/08)
A general approach to gem-difluorocyclopropenes synthesis based on the reaction of alkynes with Ruppert-Prakash reagent is reported. The proposed method is evaluated for the synthesis of a wide difluorocyclopropenes scope based on their bench lifespan and hydrolytic stability. The tolerance of the method for common functional groups was shown. Previously unavailable difluorocyclopropenes substituted with aliphatic were prepared using the proposed procedure. The retain of stability was proven by the multigram scale synthesis and further storage in the temperature interval ?78 to ?4 °C over a year. This makes them attractive building blocks and intermediates for organic synthesis. The reasons for dropping stability were defined. The relations between the structure of the substituents and the stability of the difluorocyclopropene ring were determined and discussed.
Direct Conversion of N-Alkylamines to N-Propargylamines through C-H Activation Promoted by Lewis Acid/Organocopper Catalysis: Application to Late-Stage Functionalization of Bioactive Molecules
Chan, Jessica Z.,Yesilcimen, Ahmet,Cao, Min,Zhang, Yuyang,Zhang, Bochao,Wasa, Masayuki
supporting information, p. 16493 - 16505 (2020/10/26)
An efficient catalytic method to convert an α-C-H bond of N-alkylamines into an α-C-alkynyl bond was developed. In the past, such transformations were carried out under oxidative conditions, and the enantioselective variants were confined to tetrahydroisoquinoline derivatives. Here, we disclose a method for the union of N-alkylamines and trimethylsilyl alkynes, without the presence of an external oxidant and promoted through cooperative actions of two Lewis acids, B(C6F5)3 and a Cu-based complex. A variety of propargylamines can be synthesized in high diastereo-and enantioselectivity. The utility of the approach is demonstrated by the late-stage site-selective modification of bioactive amines. Kinetic investigations that shed light on various mechanistic nuances of the catalytic process are presented.
A silicon saisai fungus amine synthesis method
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Paragraph 0026-0028; 0043-0045, (2019/04/02)
The invention provides a synthetic method for silthiopham, which belongs to the technical field of organic synthesis. The objective of the invention is to overcome the problems of complicated synthesis process, a great number of byproducts and severe environmental pollution of conventional synthetic methods for silthiopham. The synthetic method provided by the invention comprises the following steps: (1) with trimethylsilylacetylene as a raw material, under the protection of inert gas, reacting trimethylsilylacetylene with methyl chloroformate under the action of organic base so as to obtain methyl (trimethylsilyl)propiolate; (2) reacting methyl (trimethylsilyl)propiolate with allyl amine in a solvent under the action of a catalyst so as to obtain N-allyl-3-(trimethylsilyl)propiolamide; and (3) subjecting N-allyl-3-(trimethylsilyl)propiolamide with 3-mercapto-2-butanone to a heating reflux reaction under the action of an alkali catalyst and carrying out dehydration so as to obtain the final product silthiopham. The method has the advantages of usage of cheap and easily available raw materials, simple route, high yield and no usage of reagents severely polluting the environment, e.g., t-butyl nitrous acid and thionyl chloride.
A pesticide silicon saisai fungus amine synthesis method
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Paragraph 0026; 0027; 0028; 0035; 0036; 0037; 0043-0045, (2019/05/28)
The invention belongs to the technical field of organic synthesis and provides a method for synthesizing a pesticide Silthiopham. The method is used for solving the problem of the pesticide Silthiopham synthesis process at present that the yield of exchange reaction is low. The method comprises the steps of (1) enabling trimethylsilyl acetylene, which serves as a raw material, to react with methyl chloroformate in the presence of an organic base under the protection of inert gas so as to obtain trimethylsilyl methyl propiolate; (2) enabling trimethylsilyl methyl propiolate to react with 3-mercapto-2-butanone in the presence of a basic catalyst so as to obtain 4,5-dimethyl-2-(trimethylsilyl)thiophen-3-methyl formate; and (3) enabling 4,5-dimethyl-2-(trimethylsilyl)thiophen-3-methyl formate to react with allyl amine in the presence of a catalyst, thereby obtaining the end product pesticide Silthiopham. According to the method, the used raw materials are cheap and readily-available, the route is simple, the overall yield is relatively high, and the consumption of reagents causing serious environmental pollution such as tert-butyl nitrous acid (t-BuONO) and thionyl chloride is avoided.
N-triflyl-propiolamides: Preparation and transamidation reactions
Fiore, Vito A.,Maas, Gerhard
, p. 3586 - 3595 (2019/05/27)
N-Trifluoromethylsulfonyl-propiolamides have been prepared by two methods: a) N-triflation of secondary acetylenic carboxanilides, prepared in two steps from terminal alkynes, with triflic anhydride (Tf2O) and b) from terminal alkynes and an aryl or alkyl isocyanate followed by Tf2O in a consecutive one-pot reaction. The title compounds are bench-stable and insensitive to water and alcohols but amenable to transamidation reactions with a wide range of amine nucleophiles. Conversely, they are excellent reagents for the propynoylation of ammonia, primary and secondary amines, anilines, and hydrazines.
Novel one-pot synthesis of 5-alkenyl-15-alkynylporphyrins and their derivatisation to a butadiyne-linked benzoporphyrin dimer
Yamada, Hiroko,Kushibe, Kayo,Okujima, Tetsuo,Uno, Hidemitsu,Ono, Noboru
, p. 383 - 385 (2008/02/05)
5-Alkenyl-15-alkynylporphyrins have been obtained unexpectedly by [2 + 2] acid-catalyzed condensation of dipyrrylmethane and TMS propynal in addition to 5,15-dialkynylporphyrin, and the unsymmetrical porphyrin can be converted to a butadiyne-linked dimer
A facile access to 2-ethynyl-1,4-dihydropyridines via Hantzsch three-component reaction
Szemes Jr., Fridrich,Marchalin, Stefan,Pronayova, Nadezda,Daich, Adam
, p. 779 - 783 (2007/10/03)
A new synthesis of 2-ethynyl-1,4-dihydropyridine derivatives in two steps from alkyl 3-oxo-5-trimethylsilyl-4-pentynoates via the Hantzsch three-component reaction followed by an alkaline hydrolysis is described.
