36842-44-1Relevant articles and documents
Gel forming waterborne dispersion polymerization of sodium p-styrene sulfonate with glycidyl methacrylate
Dsouza, Roshan F.,Parthiban, Anbanandam
, p. 626 - 634 (2018)
Water soluble monomer like sodium p-styrene sulfonate (SSS) is copolymerized with hydrophobic and reactive monomer glycidyl methacrylate (GMA). The polymerization proceeds as dispersion and forms gels. The gel forming nature prevails even with other hydrophobic and hydrophilic monomers to form ternary polymeric systems. The swelling is dependent on polymer composition as well as the treatment history of polymers. SSS also induces ring opening of GMA to form 1,2-diols as confirmed independently by various model reactions. The ability of hydrogels to absorb various dyes indicates that owing to the anionic nature, hydrogels absorb cationic dyes nearly quantitatively. Because of their strong affinity to cationic species these hydrogel forming polymers are potentially useful in water purification applications as well as purification of proteins.
Catalytic Diastereo- and Enantioconvergent Synthesis of Vicinal Diamines from Diols through Borrowing Hydrogen
Feng, Wei,Gao, Taotao,Lau, Kai Kiat,Lin, Yamei,Pan, Hui-Jie,Yang, Binmiao,Zhao, Yu
supporting information, p. 18599 - 18604 (2021/08/09)
We present herein an unprecedented diastereoconvergent synthesis of vicinal diamines from diols through an economical, redox-neutral process. Under cooperative ruthenium and Lewis acid catalysis, readily available anilines and 1,2-diols (as a mixture of diastereomers) couple to forge two C?N bonds in an efficient and diastereoselective fashion. By identifying an effective chiral iridium/phosphoric acid co-catalyzed procedure, the first enantioconvergent double amination of racemic 1,2-diols has also been achieved, resulting in a practical access to highly valuable enantioenriched vicinal diamines.
NOVEL COMPOUNDS, FUNCTIONALISED DIOXABOROLANE OR DIOXABORINANE DERIVATIVES, METHOD FOR PREPARING SAME AND USES THEREOF
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Paragraph 0298-0301, (2020/08/05)
The invention relates to functionalised dioxaborolane or dioxaborinane derivatives of formula (I), wherein R1 is covalently bonded to the boron atom by a carbon atom; one of R2, R3, R′3 or R4 is a radical of formula —X; or one of R1, R2, R3, R′3 or R4 is a radical of formula —X; and X is a functionalised radical. The invention relates to the method for preparing same and the uses thereof.
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.
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.
Chemo- and Regioselective Functionalization of Polyols through Catalytic C(sp3)-C(sp3) Kumada-Type Coupling of Cyclic Sulfate Esters
Ramírez-Contreras, Rodrigo,Morandi, Bill
supporting information, p. 3718 - 3721 (2016/08/16)
This contribution describes a copper-catalyzed, C(sp3)-C(sp3) cross-coupling reaction of cyclic sulfate esters, a distinct class of electrophilic derivatives of polyols, with alkyl Grignard reagents to afford functionalized alcohol products in good yields. The method is operationally simple and highlights the potential of cyclic sulfate esters as highly reactive substrates in catalytic, chemoselective polyol transformations.
Osmium impregnated on magnetite as a heterogeneous catalyst for the syn-dihydroxylation of alkenes
Cano, Rafael,Pérez, Juana M.,Ramón, Diego J.
, p. 177 - 182 (2014/01/06)
A new catalyst derived from osmium has been prepared, fully characterized and tested in the dihydroxylation of alkenes. The catalyst was prepared by wet impregnation methodology of OsCl3·3H2O on a commercial micro-magnetite surface. The catalyst allowed the reaction with one of the lowest osmium loadings for a heterogeneous catalyst and was selective for the monodihydroxylation of 1,5-dienes. Moreover, the catalyst was easily removed from the reaction medium by the simple use of a magnet. The selectivity of catalyst is very high with conversions up to 99%. Preliminary kinetics studies showed a first-order reaction rate with respect to the catalyst.
Low catalyst loading in ring-closing metathesis reactions
Kadyrov, Renat
supporting information, p. 1002 - 1012 (2013/02/23)
An efficient procedure is described for ring-closing metathesis reactions. A conversion of 95 % for diethyl diallylmalonate in dilute solution could be achieved within a few minutes, reaching TOF=4173min-1, with very low loading of commercially available Ru catalysts that contained unsaturated NHC ligands. In general, only 50 to 250ppm of the catalyst is required to achieve near-quantitative conversion into a broad variety of 5-16-membered heterocyclic compounds. The practicality of this procedure was illustrated in the synthesis of 5-8-membered N-tert-butoxycarbonyl (N-Boc)- and N-para-toluenesulfonyl (N-Ts)-protected cyclic amines and 9-16-membered lactones. The synthesis of macrocyclic proline-based lactams required slightly higher catalyst loadings. Along with monocyclic products, oligomeric byproducts, mostly cyclodimers, were isolated and characterized. Getting some closure: An efficient procedure is described for ring-closing metathesis reactions in which only 50 to 250ppm of catalyst is required to effect almost-quantitative conversion into a broad range of 5-16-membered heterocyclic compounds. The practicality of this procedure was illustrated in the synthesis of 5-8-membered N-protected cyclic amines, 9-16-membered lactones, and 11-16-membered proline-based lactams. Copyright
An intramolecular Diels-Alder strategy for the asbestinins: Enantioselective total syntheses of 11-acetoxy-4-deoxyasbestinin D and asbestinin-12
Crimmins, Michael T.,Ellis, J. Michael
, p. 1649 - 1660 (2008/09/18)
(Chemical Equation Presented) The enantioselective total syntheses of 11-acetoxy-4-deoxyasbestinin D and asbestinin-12 have been completed. A glycolate aldol reaction provided a diene useful for ring-closing metathesis to form an oxonene, which was ultimately employed as a template to execute a highly stereoselective intramolecular Diels-Alder cycloaddition, forming the hydroisobenzofuran moiety. The absolute configuration of the asbestinin subclass was confirmed via these synthetic efforts.
Selective synthesis of β-hydroxy nitroethanol ethers by alcoholysis of oxiranes
Gras, Jean-Louis,Daoubi, Mourad,Collado, Isidro G.
, p. 3589 - 3598 (2008/03/13)
β-Hydroxy nitroethanol ethers are prepared by selective alcoholysis of oxiranes. The best results are obtained using a clay (monmorillonite K10) or a π-acid (TCNE) as the catalyst. Copyright Taylor & Francis Group, LLC.
