82947-13-5Relevant academic research and scientific papers
Molecular Engineering of β-Substituted Oxoporphyrinogens for Hydrogen-Bond Donor Catalysis
Chahal, Mandeep K.,Payne, Daniel T.,Matsushita, Yoshitaka,Labuta, Jan,Ariga, Katsuhiko,Hill, Jonathan P.
, p. 82 - 90 (2020)
A new class of bifunctional hydrogen-bond donor organocatalyst using oxoporphyrinogens having increased intramolecular hydrogen-bond donor distances is reported. Oxoporphyrinogens are highly non-planar rigid macrocycles containing a multiple hydrogen bond-forming binding site. In this work, we describe the first example of non-planar OxPs as hydrogen-bond donor catalysts prepared using a molecular engineering approach of the binding site for dual activation of substrates. The introduction of β-substituents is key to the catalytic activity and the catalysts are able to catalyze 1,4-conjugate additions and sulfa-Michael additions, as well as, Henry and aza-Henry reactions at low catalyst loadings (≤ 1 mol-%) under mild conditions. Preliminary mechanistic studies have been carried out and a possible reaction mechanism has been proposed based on the bi-functional activation of both substrates through hydrogen-bonding interactions.
1,3-Diamine-Derived Bifunctional Organocatalyst Prepared from Camphor
Ri?ko, Sebastijan,Svete, Jurij,?tefane, Bogdan,Perdih, Andrej,Golobi?, Amalija,Meden, An?e,Gro?elj, Uro?
supporting information, p. 3786 - 3796 (2016/12/16)
Chiral 1,2-diamines are privileged structural motifs in organocatalysis, whereas efficient 1,3-diamine-derived organocatalysts are very rare. Herein we report a highly efficient camphor-1,3-diamine-derived squaramide organocatalyst. Its catalytic activity
Bifunctional organocatalysis with squaramide-containing Dawson organo-polyoxotungstates
Lachkar, David,Lac?te, Emmanuel
, p. 113 - 116 (2016/03/22)
Two squaramide-containing organo-polyoxometalates (POMs) have been prepared, which efficiently catalyze the addition of dicarbonyl derivatives onto nitroolefins. The POM surface enhances the reactivity of the squaramide, and the hybrid acts as a bifunctio
Asymmetric synthesis of tetrahydropyridines via an organocatalytic one-pot multicomponent Michael/aza-Henry/cyclization triple domino reaction
Blümel, Marcus,Chauhan, Pankaj,Hahn, Robert,Raabe, Gerhard,Enders, Dieter
supporting information, p. 6012 - 6015 (2015/01/08)
A low loading of a quinine-derived squaramide efficiently catalyzes the triple-domino Michael/aza-Henry/cyclization reaction between 1,3-dicarbonyl compounds, β-nitroolefins, and aldimines to provide tetrahydropyridines bearing three contiguous stereogeni
A polystyrene-supported, highly recyclable squaramide organocatalyst for the enantioselective Michael addition of 1,3-dicarbonyl compounds to β-nitrostyrenes
Kasaplar, Pinar,Riente, Paola,Hartmann, Caroline,Pericas, Miquel A.
supporting information, p. 2905 - 2910 (2013/01/15)
A chiral squaramide has been supported onto a polystyrene (PS) resin through a copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction and used as a very active, easily recoverable and highly reusable organocatalyst for the asymmetric Michael additio
Catalyst-free and solvent-free Michael addition of 1,3-dicarbonyl compounds to nitroalkenes by a grinding method
Xie, Zong-Bo,Wang, Na,Wu, Ming-Yu,He, Ting,Le, Zhang-Gao,Yu, Xiao-Qi
supporting information; experimental part, p. 534 - 538 (2012/06/29)
An environmentally benign, fast and convenient protocol has been developed for the Michael addition of 1,3-dicarbonyl compounds to β-nitroalkenes in good to excellent yields by a grinding method under catalyst- and solvent-free conditions.
Acidic alumina as a useful heterogeneous catalyst in the Michael reaction of β-dicarbonyl derivatives with conjugated nitroalkenes
Ballini, Roberto,Maggi, Raimondo,Palmieri, Alessandro,Sartori, Giovanni
, p. 3017 - 3020 (2008/03/13)
Addition of a variety of 1,3-dicarbonyl derivatives to conjugated nitroalkenes was efficiently performed under heterogeneous catalysis by acidic alumina in the presence of a minimum amount of solvent (Et2O, 0.5 mL/mmol). The procedure allows sa
Michael additions of aldehydes and ketones to β-nitrostyrenes in an ionic liquid
Kotrusz, Peter,Toma, Stefan,Schmalz, Hans-Guenther,Adler, Andreas
, p. 1577 - 1583 (2007/10/03)
Michael additions of different aldehydes and ketones to β-nitrostyrene and 2-(β-nitrovinyl)thiophene in 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF6) were studied. β-Nitrostyrene was a better acceptor than 2-(β-nitrovinyl)thiophen
