115-19-5Relevant articles and documents
The role of potassium cation in the Favorskii ethynylation of acetone: Effekt of dibenzo-18-crown-6
Trofimov,Nosyreva,Mal'kina
, p. 1254 - 1259 (2005)
Macrocyclic polyether dibenzo-18-crown-6 possessing a specific affinity for potassium cation inhibits ethynylation of acetone with acetylene in the presence of KOH according to Favorskii. The inhibition becomes stronger in the presence of the complex dibenzo-18-crown-6·KOH·MeOH as catalyst (both in excess acetone and in DMSO). The effect does not originate from deactivation of acetone, for its aldol-like condensation is accelerated in the presence of both dibenzo-18-crown-6 and its complex (the selectivity of ethynylation sharply falls down). Thus, apart from the high basicity of the medium, activation of acetylene due to complex formation with potassium cation plays an important role in the Favorskii ethynylation of ketones.
Modified copolymers of bifunctional vinyl ethers with methyl vinyl sulfide as active matrices of solid superbases
Trofimov,Morozova,Mikhaleva,Markova,Tatarinova,Henkelmann
, p. 2111 - 2116 (2008)
Reactive linear and crosslinked copolymers of diethylene glycol divinyl ether and ethylene glycol vinyl glycidyl ether with methyl vinyl sulfide have been synthesized in the presence of 2,2′-azobis(isobutyronitrile) (2%, 60 °C, 45-55 h) in ～53% yield. The hydrolyzed at the residual vinyloxy and epoxy groups and oxidized at the methylthio groups copolymers upon treatment with KOH afford alkoxide (complex) and crown-like superbases. They are capable of catalyzing the acetone ethynylation, as well as the prototropic isomerization of methyl propargyl ether to allenyl methyl ether and vinylation of ethylene and diethylene glycols with acetylene.
Enantio- And Diastereodivergent Construction of 1,3-Nonadjacent Stereocenters Bearing Axial and Central Chirality through Synergistic Pd/Cu Catalysis
Huo, Xiaohong,Ma, Shengming,Xiao, Junzhe,Zhang, Jiacheng,Zhang, Wanbin,Zhao, Ling
supporting information, p. 12622 - 12632 (2021/08/31)
In contrast to the widely explored methods for the asymmetric synthesis of molecules bearing a single stereocenter or adjacent stereocenters, the concurrent construction of 1,3-stereogenic centers in an enantio- and diastereoselective manner remains a challenge, especially in acyclic systems. Herein, we report an enantio- and diastereodivergent construction of 1,3-nonadjacent stereocenters bearing allenyl axial and central chirality through synergistic Pd/Cu-catalyzed dynamic kinetic asymmetric allenylation with racemic allenylic esters. The protocol is suitable for a wide range of substrates including the challenging allenylic esters with less sterically bulky substituents and provided chiral allenylic products bearing 1,3-nonadjacent stereocenters with high levels of enantio- and diastereoselectivities (up to >20:1 dr and >99% ee). Furthermore, several representative transformations involving axial-to-central chirality transfer were conducted, affording useful structural motifs containing nonadjacent stereocenters in a diastereodivergent manner.
Separation method of 2-methyl-3-butyn-2-ol
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Paragraph 0082-0093; 0158-0160, (2020/11/01)
The invention belongs to the technical field of acetylene alcohol production, and particularly relates to a separation method of 2-methyl-3-butyn-2-ol, which comprises the following steps: pretreatinga reaction solution containing 2-methyl-3-butyn-2-ol to remove unreacted acetone and contained salt from the reaction solution to obtain a 2-methyl-3-butyn-2-ol crude product, with the content of 2,5-dimethyl-3-hexyn-2,5-diol in the reaction solution containing 2-methyl-3-butyn-2-ol being not higher than 0.1 wt%; separating and purifying the 2-methyl-3-butyn-2-ol crude product by virtue of membrane separation treatment and reduced pressure distillation treatment, so as to obtain a 2-methyl-3-butyn-2-ol product. According to the method disclosed by the invention, water in the product can be removed and the content of the 2,5-dimethyl-3-hexyn-2,5-diol can be reduced under the condition that the investment and the energy consumption are reduced, so that the 2-methyl-3-butyn-2-ol with relatively high purity and conversion rate is obtained.
Synthetic method of 3-methoxy-3-methylbutyne
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Paragraph 0012-0020, (2019/11/28)
The invention discloses a synthetic method of 3-methoxy-3-methylbutyne. The method comprises the following steps: using acetone and acetylene as starting raw materials, firstly synthesizing 3-methylbutyn-3-ol, and performing a reaction on the 3-methylbutyn-3-ol and dimethyl sulfate to obtain the 3-methoxy-3-methylbutyne. According to the synthetic method of the 3-methoxy-3-methylbutyne provided bythe invention, the raw materials used in the synthetic method have a low price and low costs and are easy to obtain, the synthetic method has a short synthetic route, a high yield, and high chemicalpurity of the obtained product, no special production equipment is needed in all reactions, and the obtained intermediate and the final product do not need to be treated by column chromatography and crystallization purification.
Base-Catalyzed Borylation/B-O Elimination of Propynols and B2pin2 Delivering Tetrasubstituted Alkenylboronates
Kuang, Zhijie,Chen, Haohua,Yan, Jianxiang,Yang, Kai,Lan, Yu,Song, Qiuling
supporting information, p. 5153 - 5157 (2018/09/12)
An efficient approach to tetrasubstituted alkenylboronates via a cascade borylation/B-O elimination of propynols and B2pin2 was disclosed. A series of tetrasubstituted alkenylboronates were readily furnished with this strategy in good yields, with further transformations leading to tetrasubstituted alkenes and β-diketones demonstrating the synthetic potential of the alkenylboronates constructed by this strategy as versatile intermediates in organic synthesis.
Method for efficiently preparing alkynol
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Paragraph 0036; 0037; 0038; 0039; 0040; 0041; 0042, (2018/12/14)
The invention relates to a method for efficiently preparing alkynol, belongs to the field of preparation of chemical intermediates and chemicals, and particularly relates to a preparation method of alkynol. The preparation method comprises the following steps that 1, alkali metal is added into an anhydrous alcohols solvent; an alcohol-alkali metal solution is prepared; 2, a compound I is added into the alcohol-alkali metal solution; uniform stirring is performed; cooling is performed to be 0 DEG C or below; 3, acetylene is introduced through being metered at normal pressure; alkynol is obtained; 4, the alkynol solution after reaction is neutralized by ammonium chloride and a same alcohol mixed suspension system; 5, the neutralized mixed suspension system is filtered; after alcohols are recovered from filter liquid, reduced pressure distillation is performed to obtain an alkynol product. The method overcomes the defect that under the existing harsh reaction conditions of high pressure,liquid ammonia and the like, the solid potassium hydroxide feeding difficulty is avoided; under the ordinary pressure condition, the ketone compounds are converted into alkynol at high conversion rate. The method has the advantages of high conversion rate, simple process and good product purity.
Convenient and highly efficient routes to 2 H-chromene and 4-chromanone derivatives: Iodine-promoted and p-toluenesulfonic acid catalyzed cascade cyclizations of propynols
Qiu, Yi-Feng,Ye, Yu-Ying,Song, Xian-Rong,Zhu, Xin-Yu,Yang, Fang,Song, Bo,Wang, Jia,Hua, Hui-Liang,He, Yu-Tao,Han, Ya-Ping,Liu, Xue-Yuan,Liang, Yong-Min
supporting information, p. 3480 - 3487 (2015/03/04)
A convenient strategy is presented for the easy preparation of a series of 2 H-chromenes under mild conditions through iodocyclization of readily accessible propynols. In addition, various 4-chromanones can be synthesized through a p-toluenesulfonic acid catalyzed cascade cyclization with high efficiency (yields up to 99%). Our developed reaction systems are proven to have good functional-group applicability and can be scaled up to gram quantities in satisfactory yields. These systems also provide a new synthetic strategy for two types of important flavonoid skeleton without using costly and toxic metal catalysts. Additionally, the resulting halides could be further exploited in subsequent palladium-catalyzed coupling reactions, so these compounds could act as potential intermediates for the construction of some valuable drug molecules.
Gold-catalyzed reactions of propargylic esters with vinylazides for the synthesis of Z- or E-configured buta-1,3-dien-2-yl esters
Wagh, Sachin Bhausaheb,Liu, Rai-Shung
supporting information, p. 15462 - 15464 (2015/10/20)
Gold-catalyzed synthesis of buta-1,3-dien-2-yl esters by the reaction of propargyl esters with vinylazides is described; the reaction mechanism is postulated to involve a vinyl attack of vinylazides at alkenyl gold carbenes.
Efficient synthesis and antibacterial activities of some novel 1,2,3-triazoles prepared from propargylic alcohols and benzyl azides
Hosseinzadeh, Rahman,Abolfazli, Mohammadreza Khadem,Mohseni, Mojtaba,Mohadjerani, Maryam,Lasemi, Zahra
, p. 1298 - 1305 (2015/04/27)
A simple and effective procedure for regioselective preparation of 1,2,3-triazoles from benzyl azides and propargylic alcohols is described using CuSO4·5H2O and sodium ascorbate. To screen the antibacterial activity of some newly synthesized triazole derivatives, minimum inhibitory concentration of 3d and 3k was evaluated against gram positive Staphylococcus aureus and Bacillus subtilis and gram negative Escherichia coli and Pseudomonas aeruginosa.
