24856-58-4Relevant articles and documents
Preparation of a Yb(III)-Incorporated porous polymer by post-Coordination: Enhancement of gas adsorption and catalytic activity
Kim, Hyungwoo,Cha, Min Chul,Park, Hyun Woo,Chang, Ji Young
, p. 5291 - 5297 (2013)
We synthesized a Yb(III)-incorporated microporous polymer (Yb-ADA) and studied its gas adsorption property and catalytic activity. The adamantane-based porous polymer (ADA) was obtained from an ethynyl-functionalized adamantane derivative and 2,5-dibromoterephthalic acid through Sonogashira-Hagihara cross-coupling. ADA had two carboxyl groups which were used for Yb(III) coordination under basic conditions. The Brunauer-Emmett-Teller (BET) surface area of ADA was 970 m2 g-1. As Yb(III) ions were incorporated into ADA, the surface area of the polymer (Yb-ADA) was reduced to 885 m2 g-1. However, Yb-ADA exhibited a significantly enhanced CO2 adsorption capacity despite the reduction of surface area. The CO2 uptakes of ADA and Yb-ADA were 1.56 and 2.36 mmol g-1 at 298 K, respectively. The H2 uptake of ADA also increased after coordination with Yb(III) from 1.15 to 1.40 wt % at 77 K. Yb-ADA showed high catalytic activity in the acetalization of 4-bromobenzaldehyde and furfural with trimethyl orthoformate and could be reused after recovery without severe loss of activity.
Preparation method of acetal or ketal compound
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Paragraph 0021-0030; 0100-0105, (2020/04/22)
The invention discloses a preparation method of an acetal or ketal compound. The preparation method comprises the following steps: oscillating aldehyde or ketone, alcohol and a catalyst at 60 DEG C, and carrying out post-treatment after the reaction is finished to obtain the acetal compound, wherein the catalyst comprises alpha-chymotrypsin, the aldehyde or ketone has a structure represented by acompound A, R1 and R2 are respectively and independently selected from aryl, H and alkyl, the alcohol has a structure represented by a compound B, and R3 is selected from saturated alkane. The preparation method provided by the invention is catalyzed by alpha-chymotrypsin, is mild in reaction condition, simple in operation process, low in cost and environment-friendly, and has popularization and application values.
Photochemical synthesis of acetals utilizing Schreiner's thiourea as the catalyst
Kokotos, Christoforos G.,Nikitas, Nikolaos F.,Spiliopoulou, Nikoleta
supporting information, p. 3539 - 3545 (2020/06/25)
Acetalization of aldehydes is an area of great importance in Organic Chemistry for both synthetic and biological puproses. Herein, we report a mild, inexpensive and green photochemical protocol, where Schreiner's thiourea (N,N′-bis[3,5-bis(trifluoromethyl)-phenyl]-thiourea) is utilized as the catalyst and cheap household lamps as the light source. A variety of aromatic and aliphatic aldehydes were converted into acetals in good to high yields (23 examples, 36-96% yield) and an example of the synthesis of a cyclic acetal is provided. The reaction mechanism was also studied.