50888-84-1Relevant academic research and scientific papers
Rational design of simple organocatalysts for the hsicl3 enantioselective reduction of (E)-n-(1-phenylethylidene)aniline
Burguete, Maria Isabel,García-Verdugo, Eduardo,Luis, Santiago V.,Maciá, María,Martí-Centelles, Vicente,Porcar, Raúl
supporting information, (2021/11/30)
Prolinamides are well-known organocatalysts for the HSiCl3 reduction of imines; however, custom design of catalysts is based on trial-and-error experiments. In this work, we have used a combination of computational calculations and experimental work, including kinetic analyses, to properly understand this process and to design optimized catalysts for the benchmark (E)-N-(1-phenylethylidene)aniline. The best results have been obtained with the amide derived from 4-meth-oxyaniline and the N-pivaloyl protected proline, for which the catalyzed process is almost 600 times faster than the uncatalyzed one. Mechanistic studies reveal that the formation of the component supramolecular complex catalyst-HSiCl3-substrate, involving hydrogen bonding breaking and costly conformational changes in the prolinamide, is an important step in the overall process.
Borinic Acid Catalysed Reduction of Tertiary Amides with Hydrosilanes: A Mild and Chemoselective Synthesis of Amines
Chardon, Aurélien,Mohy El Dine, Tharwat,Legay, Rémi,De Paolis, Micha?l,Rouden, Jacques,Blanchet, Jér?me
supporting information, p. 2005 - 2009 (2017/02/19)
A reduction of various aryl, alkyl, and α,β-unsaturated amides with phenylsilane, catalysed by a borinic acid, is reported. The unprecedented reaction was carried out under very mild conditions and led to useful amines. Furthermore, the reaction tolerates a variety of functional groups. Initial investigations implicated that an intermediate diarylhydroborane is involved in the reaction mechanism.
Investigation of a novel diamine based chiral auxiliary in the asymmetric alkylation of ketones
Clarke, Sarah L.,McSweeney, Christina M.,McGlacken, Gerard P.
, p. 356 - 361 (2014/04/03)
A novel chiral auxiliary containing a pyrrolidine ring has been utilised in the preparation of various chiral ketones with good to excellent enantioselectivities (up to 92%). It has been successfully employed in aldol and Michael reactions giving moderate to high selectivity.
Amides in one pot from Carboxylic Acids and Amines via Sulfinylamides
Bai, Jianfei,Zambron, Bartosz K.,Vogel, Pierre
supporting information, p. 604 - 607 (2014/04/03)
An efficient method has been developed for the direct amidification of carboxylic acids via sulfinylamides preformed in situ by the reaction of pure amines with prop-2- ene-1-sulfinyl chloride. The method can be applied to aliphatic acids, including pivalic acid, aromatic acids, and primary and secondary amines. It is compatible with acids bearing unprotected alcohol, phenol, and ketone moieties and applicable to the synthesis of peptides. It does not induce their a-epimerization.
Prolylprolinol-catalyzed asymmetric michael addition of aliphatic aldehydes to nitroalkenes
Lu, Dengfu,Gong, Yuefa,Wang, Weizhou
supporting information; experimental part, p. 644 - 650 (2010/06/20)
Several novel prolylprolinol catalysts have been designed and synthesized. This type of compound showed high catalytic efficiency on pro-moting the direct addition of unmodified aldehydes to nitroalkenes. Among the catalysts surveyed, the least bulky memb
Highly regio- and enantioselective organocatalytic conjugate addition of alkyl methyl ketones TO A β-silylmethylene malonate
Chowdhury, Raghunath,Ghosh, Sunil K.
supporting information; experimental part, p. 3270 - 3273 (2009/12/01)
(S)-N-(2-Pyrrolidinylmethyl)pyrrolidine/trifluoroacetic acid (3:1) combination catalyzed the direct addition of alkyl methyl ketones to β-dimethyl(phenyl)silylmethylene malonate at the methyl terminal with high yield and excellent regio- and enantioselectivity. The silyl group played crucial roles in regioselection and substrate reactivity.
A highly enantioselective organocatalyst for the Michael addition of cyclic ketones to nitroolefins
Zhu, Ming-Kui,Cun, Lin-Feng,Mi, Ai-Qiao,Jiang, Yao-Zhong,Gong, Liu-Zhu
, p. 491 - 493 (2007/10/03)
Enantiomerically pure triamine 2, which catalyses the Michael addition of cyclic ketones to nitroolefins with high diastereoselectivity (up to 99:1) and enantioselectivity (up to 91% ee), was designed and prepared.
Small organic molecule catalyzed enantioselective direct aldol reaction in water
Chimni, Swapandeep Singh,Mahajan, Dinesh
, p. 2108 - 2119 (2007/10/03)
Protonated pyrrolidine based small organic molecules have been designed and evaluated for the asymmetric direct aldol reaction in water. The designed organocatalysts are multifunctional in nature and exploit the combined effect of hydrogen bonding and hydrophobic interactions for enantioselective catalysis in water. As a result a unique direct asymmetric aldol reaction in water catalyzed by a small organic molecule having an amide linkage has been developed. The developed catalyst affords chiral β-hydroxyketones in good yields (93%) and enantioselectivities (upto 62%) in water.
Amidic derivatives of (R)-glycerophosphoryl-(S)-serine or of its diacyl derivative, process for their preparation and relative pharmaceutical compositions for the improvement of the learning processes
-
, (2008/06/13)
Amidic derivatives of (R)-glycerophosphoryl-(S)-serine or of its diacyl derivative, a process for their preparation, and relative pharmaceutical compositions, containing said derivatives as their active principle for the improvement of learning and memory processes.
Structure activity relationship of inhibitors specific for prolyl endopeptidase.
Yoshimoto,Tsuru,Yamamoto,Ikezawa,Furukawa
, p. 37 - 43 (2007/10/02)
Structural requirements of N-blocked L-proline derivatives as specific inhibitors for prolyl endopeptidase were investigated using a series of substrate analogs. Replacement of L-proline by its D-isomer remarkably reduced the inhibition. Introduction of a sulfur atom in proline and/or in the penultimate pyrrolidine rings significantly increased the inhibition, but the introduction of oxygen rather diminished the activity. A peptide linkage (acid-amide bond) between the proline and the pyrrolidine ring was also required to keep the inhibitory activity. A benzyloxycarbonyl group was most effective as an N-blocked component of the inhibitors.
