497-06-3Relevant articles and documents
Preparation method of vinylethylene sulfite
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Paragraph 0033-0034, (2021/03/31)
The invention belongs to the field of additives, and particularly relates to a preparation method of vinylethylene sulfite. The invention discloses a preparation method of vinylethylene sulfite, whichcomprises the following step: reacting 3-butylene-1,2-diol with thionyl chloride to obtain vinylethylene sulfite. The preparation method has the advantages of simple operation, easily available raw materials, greenness, environmental protection, and great implementation value and social and economic benefits.
Palladium-catalyzed stereoselective (3 + 2) cycloaddition of vinylethylene carbonates with cyclicN-sulfonyl ketimines
Gao, Xing,Zhu, Dongyu,Jiang, Feng,Liao, Jianning,Wang, Wei,Wu, Yongjun,Zheng, Lufei,Guo, Hongchao
supporting information, p. 4877 - 4881 (2021/06/16)
A diastereoselective (3 + 2) cycloaddition ofN-sulfonyl ketimines with vinylethylene carbonates (VECs) in the presence of Pd2dba3·CHCl3and PPh3has been developed. The reaction of various substituted VECs and diverse cyclicN-sulfonyl ketimines proceeded smoothly under mild conditions, giving highly functionalized oxazolidine frameworks in good to excellent yields with moderate to good diastereoselectivities. With the use of spiroketal-based diphosphine SKP as a chiral ligand, an asymmetric version of the current (3 + 2) cycloaddition was achieved, and chiral products were obtained in >99% ee in most cases.
An Amphiphilic (salen)Co Complex – Utilizing Hydrophobic Interactions to Enhance the Efficiency of a Cooperative Catalyst
Solís-Mu?ana, Pablo,Salam, Joanne,Ren, Chloe Z.-J.,Carr, Bronte,Whitten, Andrew E.,Warr, Gregory G.,Chen, Jack L.-Y.
supporting information, p. 3207 - 3213 (2021/06/01)
An amphiphilic (salen)Co(III) complex is presented that accelerates the hydrolytic kinetic resolution (HKR) of epoxides almost 10 times faster than catalysts from commercially available sources. This was achieved by introducing hydrophobic chains that increase the rate of reaction in one of two ways – by enhancing cooperativity under homogeneous conditions, and increasing the interfacial area under biphasic reaction conditions. While numerous strategies have been employed to increase the efficiency of cooperative catalysts, the utilization of hydrophobic interactions is scarce. With the recent upsurge in green chemistry methods that conduct reactions ‘on water’ and at the oil-water interface, the introduction of hydrophobic interactions has potential to become a general strategy for enhancing the catalytic efficiency of cooperative catalytic systems. (Figure presented.).
Olefin reaction in the catalyst and the olefin production
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Paragraph 0145-0146; 0149, (2020/10/31)
PROBLEM TO BE SOLVED: To provide a catalyst for obtaining an olefin in high selectivity with a vicinal diol as a raw material.SOLUTION: A catalyst for olefination reaction for use in a reaction to produce an olefin by a reaction of a polyol, having two adjacent carbon atoms each having a hydroxy group, with hydrogen comprises: a carrier; at least one oxide selected from the group consisting of oxides of the group 6 elements and oxides of the group 7 elements supported on the carrier; and at least one metal selected from the group consisting of silver, iridium, and gold supported on the carrier.SELECTED DRAWING: None
Asymmetric Synthesis of N-Fused 1,3-Oxazolidines via Pd-Catalyzed Decarboxylative (3+2) Cycloaddition
Ahn, Hye-In,Cho, Ho-Jun,Kim, Ju Hyun,Park, Jong-Un,Xuan, Zi
supporting information, (2020/04/22)
Efficient synthesis of optically active N-fused 1,3-oxazolidines containing quaternary and tertiary stereocenters was achieved via Pd-catalyzed asymmetric (3+2) cycloadditions of sulfamate-derived cyclic imines and vinylethylene carbonates. Using a chiral phosphoramidite ligand, the cycloadditions proceeded effectively providing sulfamidate-fused 1,3-oxazolidines in high yields (up to 96%) with stereoselectivities (up to 25:1 dr; >99% ee). Additionally, the scale-up reaction and further transformations of the product were also achieved demonstrating the synthetic utility toward the construction of useful heterocycles such as chiral oxazoline bearing a quaternary stereocenter. (Figure presented.).
Pd-Catalyzed Decarboxylative Olefination: Stereoselective Synthesis of Polysubstituted Butadienes and Macrocyclic P-glycoprotein Inhibitors
Chen, Xiangyang,Hao, Jiping,Houk, K. N.,Li, Yingzi,Lou, Liguang,Quan, Haitian,Song, Bichao,Wang, Lu,Xia, Yuanzhi,Xie, Peipei,Xu, Zhongliang,Yang, Weibo
supporting information, p. 9982 - 9992 (2020/06/27)
The efficient and stereoselective synthesis of polysubstituted butadienes, especially the multifunctional butadienes, represents a great challenge in organic synthesis. Herein, we wish to report a distinctive Pd(0) carbene-initiated decarboxylative olefination approach that enables the direct coupling of diazo esters with vinylethylene carbonates (VECs), vinyl oxazolidinones, or vinyl benzoxazinones to afford alcohol-, amine-, or aniline-containing 1,3-dienes in moderate to high yields and with excellent stereoselectivity. This protocol features operational simplicity, mild reaction conditions, a broad substrate scope, and gram-scalability. Notably, a structurally unique allylic Pd(II) intermediate was isolated and characterized. DFT calculation and control experiments demonstrated that a rare Pd(0) carbene intermediate could be involved in this reaction. Moreover, the polysubstituted butadienes as novel building blocks were unprecedentedly assembled into macrocycles, which efficiently inhibited the P-glycoprotein and dramatically reversed multidrug resistance in cancer cells by 190-fold.
Transfer hydrogenation of cyclic carbonates and polycarbonate to methanol and diols by iron pincer catalysts
Liu, Xin,De Vries, Johannes G.,Werner, Thomas
, p. 5248 - 5255 (2019/10/11)
Herein, we report the first example on the use of an earth-abundant metal complex as the catalyst for the transfer hydrogenation of cyclic carbonates to methanol and diols. The advantage of this method is the use of isopropanol as the hydrogen source, thus avoiding the handling of flammable hydrogen under high pressure. The reaction offers an indirect route for the reduction of CO2 to methanol. In addition, poly(propylene carbonate) was converted to methanol and propylene glycol. This methodology can be considered as an attractive opportunity for the chemical recycling of polycarbonates.
A versatile biobased continuous flow strategy for the production of 3-butene-1,2-diol and vinyl ethylene carbonate from erythritol
Tshibalonza, Nelly Ntumba,Gérardy, Romaric,Alsafra, Zouheir,Eppe, Gauthier,Monbaliu, Jean-Christophe M.
supporting information, p. 5147 - 5157 (2018/11/26)
A versatile, tunable and robust continuous flow procedure for the deoxydehydration (DODH) of biobased erythritol toward 3-butene-1,2-diol is described. The procedure relies on specific assets of multistep continuous flow processing. Detailed mechanistic and computational studies on erythritol show that either 3-butene-1,2-diol or butadiene are obtained in high selectivity and yield on demand, as a function of the DODH reagent/substrate ratio and of the process parameters. Short reaction times (1-15 min) at high temperature (225-275 °C) and moderate pressure are reported. 3-Butene-1,2-diol is then further converted downstream into its corresponding carbonate, i.e. 4-vinyl-1,3-dioxolan-2-one (vinyl ethylene carbonate), an important industrial building block. The carbonation step uses a supported organocatalyst, and could be directly concatenated to the first DODH step. This unprecedented procedure also relies on a unique combination of on- and off-line analytical protocols for reaction monitoring and product quantification, and offers a biobased strategy toward important industrial building blocks otherwise petrosourced.
Enzyme-mediated enantioselective hydrolysis of 1,2-diol monotosylate derivatives bearing an unsaturated substituent
Matsumoto,Oohana,Hashimoto,Usuda,Shimoda,Ohshima,Suzuki,Togawa
supporting information, p. 3981 - 3988 (2018/06/15)
We have succeeded in the easy preparation of optically active 1,2-diol monotosylates bearing an unsaturated substituent via enzymatic hydrolysis. Lipase PS quickly catalyzes the hydrolyses of 2-acetoxybut-3-enyl tosylate, which has a double bond, and 2-acetoxybut-3-ynyl tosylate, which has a triple bond, with excellent enantioselectivity to afford the corresponding optically active compounds. The reaction is also applicable to acetates with a longer chain, which has a double bond at the terminus. To demonstrate the applicability of this method, enantiomerically pure (R)-massoialactone, a natural coconut flavor, has been synthesized from racemic 2-acetoxypent-4-enyl tosylate in several steps. Furthermore, the enzyme can recognize the stereochemistry of olefins, and the (Z)-alkenyl structure is more suitable for the enantioselective hydrolysis than the (E)-isomer.
Formal [5+3] Cycloaddition of Zwitterionic Allylpalladium Intermediates with Azomethine Imines for Construction of N,O-Containing Eight-Membered Heterocycles
Yuan, Chunhao,Wu, Yang,Wang, Dongqi,Zhang, Zhenhua,Wang, Chang,Zhou, Leijie,Zhang, Cheng,Song, Baoan,Guo, Hongchao
supporting information, p. 652 - 658 (2017/12/26)
A formal [5+3] cycloaddition of zwitterionic allylpalladium intermediates with 1,3-dipoles is developed, providing N,O-containing eight-membered heterocyclic compounds in high yields. Catalytically generated zwitterionic allylpalladium intermediates in situ from vinylethylene carbonates or vinyloxiranes acted as dipolarophile. (Figure presented.).
