19444-84-9Relevant articles and documents
Synthesis of α-hydroxy-γ-butyrolactones from acrylates and 1,3-dioxolanes using N-hydroxyphthalimide (NHPI) as a key catalyst
Kagayama, Takashi,Sakaguchi, Satoshi,Ishii, Yasutaka
, p. 3687 - 3689 (2005)
A new route to α-hydroxy-γ-butyrolactones through three-component radical coupling of 1,3-dioxoranes, acrylates, and molecular oxygen using N-hydroxyphthalimide (NHPI) as a key catalyst has been developed. For example, the addition of 1,3-dioxarane to methyl acrylate under dioxygen by NHPI followed by catalytic hydrogenation of the resulting adduct on Pd/C afforded α-hydroxy-γ-butyrolactone in good yield. This method provides a facile approach to α-hydroxy-γ-butyrolactones, which are difficult to synthesize by conventional methods.
Ru/SiO2 Catalyst for Highly Selective Hydrogenation of Dimethyl Malate to 1,2,4-Butanetriol at Low Temperatures in Aqueous Solvent
Chen, Can,Jiang, Junxiang,Li, Guangci,Li, Xuebing,Wang, Da,Wang, Zhong,Yu, Pei
, (2022/01/12)
Catalytic selective hydrogenation of esterified malic acid to produce 1,2,4-butanetriol (1,2,4-BT) using H2 as the reducing reagent suffers from the low 1,2,4-BT selectivity. Here, Ru/SiO2 catalyst was employed for selective hydrogenation of dimethyl malate (DM) to produce 1,2,4-BT, which gave abnormal high DM conversion (100%) and 1,2,4-BT selectivity (92.4%) in aqueous solvent at 363?K, especially, the 1,2,4-BT yield even is higher than the optimal catalyst reported (Ru-Re, 79.8%). The reaction pathways for the DM hydrogenation on Ru/SiO2 were also proposed, suggesting that extremely high 1,2,4-BT selectivity require for the much high hydrogenation rates at low temperatures, where side-reaction transesterification rates are relatively low. The extremely high hydrogenation activity and 1,2,4-BT selectivity on Ru/SiO2 in aqueous solvent at low temperatures arise from that H2O may coordinate to Ru2+ and prevent the reduction of Ru2+ to Ru under high H2 pressure. Ru/SiO2 surface presents abundant Ru2+ in aqueous solvent, can activate H2 through heterolytic cleavage mode to form hydride, which can significantly increase hydrogenation rates of C = O groups at low temperatures. In addition, the activity and 1,2,4-BT selectivity on Ru/SiO2 catalyst only reduced by 2.3% and 2.6%, respectively over a period of 550?h. Graphical Abstract: [Figure not available: see fulltext.]
Preparation method of DL-hydroxy selenomethionine
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Paragraph 0008; 0018-0019, (2021/06/02)
The invention belongs to the field of preparation of organic compounds. The invention provides a preparation method of DL-hydroxy selenomethionine. The method is characterized in that gamma-butyrolactone is used as a raw material, alpha-hydroxyl-gamma-butyrolactone is synthesized through alpha-bromination and hydroxylation, and then the alpha-hydroxyl-gamma-butyrolactone reacts with sodium methyl selenol to obtain the DL-hydroxyl selenomethionine. The method has the advantages of easily available raw materials, mild reaction conditions and low cost, and is suitable for large-scale preparation of DL-hydroxyselenomethionine.
Preparation method of alpha-hydroxyl-gamma-butyrolactone
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Paragraph 0024; 0026, (2021/06/13)
The invention belongs to the field of preparation of organic compounds, and provides a preparation method of alpha-hydroxyl-gamma-butyrolactone. The method is characterized in that malic acid is used as a raw material, and alpha-hydroxyl-gamma-butyrolactone is synthesized with high yield through four steps of reactions, namely, carboxyl and alpha-hydroxyl protection, beta-carboxyl reduction, protecting group removal and internal esterification. The method has the advantages of easily available raw materials, mild reaction conditions and low cost, and is suitable for large-scale preparation of alpha-hydroxy-gamma-butyrolactone.
Visible light-induced Minisci reaction through photoexcitation of surface Ti-peroxo species
Naniwa, Shimpei,Yamamoto, Akira,Yoshida, Hisao
, p. 3376 - 3384 (2021/06/06)
Photocatalytic Minisci-type functionalization of pyridine with tetrahydrofuran (THF) proceeded using hydrogen peroxide (H2O2) and a TiO2photocatalyst under acidic conditions. Under UV light (λ= 360 nm), the reaction selectivity based on pyridine (Spy) was >99% while the selectivity based on THF (STHF) was low such as 19%. In contrast, under visible light (λ= 400 or 420 nm)Spywas similarly high (>99%) andSTHFwas two times higher than that under UV light. A surface peroxo complex formed upon contact of hydrogen peroxide with the TiO2surface can be selectively photoexcited by visible light to inject the photoexcited electron to the conduction band of TiO2. The electron can reduce H2O2to a reactive oxygen species (ROS) and promote selectively the Minisci-type cross-coupling reaction between pyridinium ions and THF. A reaction test with a hole scavenger (methanol) evidenced that the hole oxidation of H2O2under UV light is responsible for the lower selectivity, in other words, the higher selectivity under visible light would be due to suppression of the hole oxidation of H2O2. These results demonstrate a novel way to improve the selectivity of the photocatalytic cross-coupling reaction by using H2O2as an oxidant with the photoexcitation of surface Ti-peroxo species on TiO2
CYCLIC PHOSPHATE SUBSTITUTED NUCLEOSIDE DERIVATIVES AND METHODS OF USE THEREOF FOR THE TREATMENT OF VIRAL DISEASES
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Page/Page column 47-48, (2018/04/11)
The present invention relates to Cyclic Phosphate Substituted Nucleoside Derivatives of Formula (I), and pharmaceutically acceptable salts thereof, wherein A, B, Q, V, R1, R2 and R3 are as defined herein. The present invention also relates to compositions comprising a Cyclic Phosphate Substituted Nucleoside Derivative, and methods of using the Cyclic Phosphate Substituted Nucleoside Derivatives for treating or preventing HCV infection in a patient.
Shape-selective Valorization of Biomass-derived Glycolaldehyde using Tin-containing Zeolites
Tolborg, S?ren,Meier, Sebastian,Saravanamurugan, Shunmugavel,Fristrup, Peter,Taarning, Esben,Sádaba, Irantzu
, p. 3054 - 3061 (2016/11/17)
A highly selective self-condensation of glycolaldehyde to different C4 molecules has been achieved using Lewis acidic stannosilicate catalysts in water at moderate temperatures (40–100 °C). The medium-sized zeolite pores (10-membered ring framework) in Sn-MFI facilitate the formation of tetrose sugars while hindering consecutive aldol reactions leading to hexose sugars. High yields of tetrose sugars (74 %) with minor amounts of vinyl glycolic acid (VGA), an α-hydroxyacid, are obtained using Sn-MFI with selectivities towards C4 products reaching 97 %. Tin catalysts having large pores or no pore structure (Sn-Beta, Sn-MCM-41, Sn-SBA-15, tin chloride) led to lower selectivities for C4 sugars due to formation of hexose sugars. In the case of Sn-Beta, VGA is the main product (30 %), illustrating differences in selectivity of the Sn sites in the different frameworks. Under optimized conditions, GA can undergo further conversion, leading to yields of up to 44 % of VGA using Sn-MFI in water. The use of Sn-MFI offers multiple possibilities for valorization of biomass-derived GA in water under mild conditions selectively producing C4 molecules.
Influence of the Interaction between a Tin Catalyst and an Accelerator on the Formose-Inspired Synthesis of α-Hydroxy-γ-butyrolactone
Yamaguchi, Sho,Matsuo, Takeaki,Motokura, Ken,Miyaji, Akimitsu,Baba, Toshihide
, p. 1386 - 1391 (2016/04/20)
In this study, we focused on the tin-catalyzed transformation of formaldehyde into α-hydroxy-γ-butyrolactone (HBL) in the presence of an α-hydroxy carbonyl compound as the accelerator. The screening of various accelerators aided in clarifying the structural prerequisites of the accelerator for the formose-inspired synthesis of HBL. To investigate the influence of the interactions between the tin metal and the accelerator on the catalytic activity, we performed a deuterium-exchange experiment with α-hydroxyacetophenone followed by in situ 119Sn NMR spectroscopy and X-ray absorption fine structure measurements. On the basis of the experimental results, we proposed a reaction mechanism to obtain HBL.
Process for treating homoserin compounds
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Paragraph 0295-0299, (2017/01/02)
The present invention relates to the preparation of a useful compound which can be used as an intermediate product for preparing an important compound in the industrial field from a homoserine-based compound and provides a process for treating a homoserine-based compound, capable of simply mass producing a useful compound from a homoserine-based compound with excellent efficiency.(AA) Homoserine-based compound(BB) Product(CC) GBL derivative(DD) Halo-GBL(EE, FF, GG) GBL puranone(HH) Puranone(II) Dialkyl succinate(JJ) Step 1(KK) Step 2(LL) Step 3(MM) Step 4(NN) Step 5(OO) Step 6(PP) Step 7COPYRIGHT KIPO 2016
Solid Lewis acids catalyze the carbon-carbon coupling between carbohydrates and formaldehyde
Van De Vyver, Stijn,Odermatt, Caroline,Romero, Kevin,Prasomsri, Teerawit,Román-Leshkov, Yuriy
, p. 972 - 977 (2015/09/08)
The development of catalytic C-C bond formation schemes based on renewable substrates is important for defining sustainable paradigms for chemical manufacturing. With a few exceptions, aldol condensation reactions between biomass-derived platform chemicals have received little attention so far. Here the C-C coupling between 1,3-dihydroxyacetone (DHA) and formaldehyde into α-hydroxy-γ-butyrolactone (HBL) using Sn-Beta is demonstrated. Reactivity studies, coupled with spectroscopic and computational analyses, show that the formation of HBL proceeds by soft enolization of DHA followed by an aldol addition of formaldehyde to the Sn-enolate intermediate, generating erythrulose as an intermediate species. Isotopic labeling is used to reveal the position where formaldehyde is incorporated into HBL, providing further support for our proposed mechanism. Finally, combining the C-C coupling reaction with transfer hydrogenation of formaldehyde has allowed us to expand the substrate scope to include polyols glycerol and ethylene glycol.
