ChemInform Abstract: Functionalized Proline with Double Hydrogen Bonding Potential: Highly Enantioselective Michael Addition of Carbonyl Compounds to β-Nitrostyrenes in Brine.

ChemInform ◽  
2010 ◽  
Vol 41 (52) ◽  
pp. no-no
Author(s):  
Satyajit Saha ◽  
Saona Seth ◽  
Jarugu Narasimha Moorthy
Keyword(s):  
Hydrogen Bonding ◽  
Michael Addition ◽  
Carbonyl Compounds ◽  
Hydrogen Bonding Potential ◽  
Double Hydrogen

IR study on double hydrogen bonding in dichloromethane

1992 ◽  
Vol 275 ◽  
pp. 203-210 ◽  
Author(s):  
Jan Cz. Dobrowolski ◽  
Michał H. Jamróz ◽  
Aleksander P. Mazurek
Keyword(s):  
Hydrogen Bonding ◽  
Ir Study ◽  
Double Hydrogen

Enantioselective Protonation in the Sulfa-Michael Addition Using Chiral Squaramides as Hydrogen-Bonding Organocatalysts

Synlett ◽  
2011 ◽  
Vol 2012 (02) ◽  
pp. 314-316 ◽  
Author(s):  
Fener Chen ◽  
Le Dai ◽  
Hongjun Yang ◽  
Jingze Niu
Keyword(s):  
Hydrogen Bonding ◽  
Michael Addition

ChemInform Abstract: Fast, Solvent-Free and Hydrogen-Bonding-Mediated Asymmetric Michael Addition in a Ball Mill.

ChemInform ◽  
2012 ◽  
Vol 43 (34) ◽  
pp. no-no
Author(s):  
Yi-Feng Wang ◽  
Ru-Xiang Chen ◽  
Ke Wang ◽  
Bin-Bin Zhang ◽  
Zhao-Bo Li ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Michael Addition ◽  
Ball Mill ◽  
Solvent Free ◽  
Asymmetric Michael Addition

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.

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