A nanoporous metal–organic framework as a renewable size-selective hydrogen-bonding catalyst in water

2019 ◽  
Vol 48 (31) ◽  
pp. 11855-11861 ◽  
Author(s):  
Yanhong Liu ◽  
Ju Ma ◽  
Pengyan Wu ◽  
Jia-Jia Zheng ◽  
Xueqin Tian ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Michael Addition ◽  
Addition Reaction ◽  
Metal Organic Framework ◽  
Michael Addition Reaction ◽  
Size Selectivity ◽  
Nanoporous Metal ◽  
Metal Organic ◽  
Reaction In Water

A new squaramide-containing nanoporous MOF as a bifunctional hydrogen-bond catalyst exhibits high size-selectivity and good renewability for a Michael addition reaction in water.

Novel Polyaspartic Ester Polyureas Based on Flexible Polyaspartic Ester

2011 ◽  
Vol 197-198 ◽  
pp. 1294-1298
Author(s):  
Ping Lu ◽  
Wei Bo Huang ◽  
Xue Qiang Ma ◽  
Xu Dong Liu
Keyword(s):  
Mechanical Properties ◽  
Molecular Weight ◽  
Hydrogen Bonding ◽  
Molecular Weight Distribution ◽  
Michael Addition ◽  
Weight Distribution ◽  
Addition Reaction ◽  
Chain Extender ◽  
Michael Addition Reaction ◽  
Ft Ir

New polyaspartic ester (PAE) chain extender named PAE-f was prepared via two steps of Michael addition reactions:(1) Michael addition reaction between 4,4’-methylenebis(2-methyl cyclohexyl amine) (Laromin C260) and excessive dialkyl maleates（DEF）; (2) The Michael addition reaction of the residual dialkyl maleates of step (1) with polyester polyamine Jeffamine D230. The two-steps method proposed could reduce the reaction time in comparison with the current one step Michael addition reaction method, thus satisfying the industrialized production. New PAE based polyureas were synthesized by reacting the PAE-f chain extender with aliphatic polyisocyanates 4,4’-diisocyanato dicyclohexylmethane (H12MDI) / polyester polyamine Jeffamine D2000 prepolymer at room temperature. FT-IR and GPC were employed to characterize the new PAE prepared, and the morphology, molecular weight distribution and mechanical properties of the prepared PAE based polyureas were investigated by means of FT-IR and GPC. The FT-IR results indicated that the hydrogen bonding degree of amidogen groups in hard segments of the prepared polyureas were high, the length of hydrogen bonding were 0.305nm～0.306nm. The GPC experimental results show that the weight average molecular weight of the PAE-f based polyureas were 4.95×104～6.05×104,Mw/Mn were 1.65～1.97, the molecular weight distribution were relatively narrow. The mechanical properties demonstrated that the tensile strength were 14.7～22.5MPa, Elongation at break were 306～511%, Yang’s modulus were 67～127MPa, Shore A hardness were 64～83. The mechanical properties confirmed that the polyureas based on PAE-f were kinds of elastomeric materials with satisfied flexibility, strength, module and hardness.

Pyridine-grafted graphene oxide: a reusable acid–base bifunctional catalyst for the one-pot synthesis of β-phosphonomalonates via a cascade Knoevenagel–phospha Michael addition reaction in water

RSC Advances ◽  
2015 ◽  
Vol 5 (117) ◽  
pp. 96532-96538 ◽  
Author(s):  
Sara Sobhani ◽  
Farzaneh Zarifi
Keyword(s):  
Graphene Oxide ◽  
Michael Addition ◽  
Addition Reaction ◽  
Bifunctional Catalyst ◽  
Michael Addition Reaction ◽  
Acid Base ◽  
One Pot ◽  
One Pot Synthesis ◽  
The One ◽  
Reaction In Water

Py–GO as a new acid–base bifunctional catalyst was synthesized and employed for the one-pot synthesis of β-phosphonomalonates in water.

A novel chiral surfactant-type metallomicellar catalyst for asymmetric Michael addition in water

2020 ◽  
Vol 56 (75) ◽  
pp. 11118-11121
Author(s):  
Xinping Liang ◽  
Yang Gui ◽  
Kuiliang Li ◽  
Jindong Li ◽  
Zhenggen Zha ◽  
...  
Keyword(s):  
Michael Addition ◽  
Addition Reaction ◽  
Michael Addition Reaction ◽  
Asymmetric Michael Addition ◽  
Reaction In Water

A new chiral surfactant-type metallomicellar catalyst was prepared and applied to an asymmetric Michael addition reaction in water.

Cupin Variants as Macromolecular Ligand Library for Stereoselective Michael Addition of Nitroalkanes

2019 ◽  
Author(s):  
Nobutaka Fujieda ◽  
Miho Yuasa ◽  
Yosuke Nishikawa ◽  
Genji Kurisu ◽  
Shinobu Itoh ◽  
...  
Keyword(s):  
Michael Addition ◽  
In Silico ◽  
Addition Reaction ◽  
Single Point ◽  
Point Mutations ◽  
Unsaturated Ketone ◽  
Michael Addition Reaction ◽  
Beta Barrel ◽  
Cupin Superfamily ◽  
Single Point Mutations

Cupin superfamily proteins (TM1459) work as a macromolecular ligand framework with a double-stranded beta-barrel structure ligating to a Cu ion through histidine side chains. Variegating the first coordination sphere of TM1459 revealed that H52A and H54A/H58A mutants effectively catalyzed the diastereo- and enantio-selective Michael addition reaction of nitroalkanes to an α,β-unsaturated ketone. Moreover, in silico substrate docking signified C106N and F104W single-point mutations, which inverted the diastereoselectivity of H52A and further improved the stereoselectivity of H54A/H58A, respectively.

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