91797-84-1Relevant articles and documents
Rhodium-Catalyzed oxidative amidation of sterically hindered aldehydes and alcohols
Nguyen, Trang T.,Hull, Kami L.
, p. 8214 - 8218 (2018/05/23)
A rhodium-catalyzed oxidative amidation reaction has been developed with sterically hindered aldehydes and alcohols for the synthesis of amides containing a quaternary carbon at the α position. A variety of amine nucleophiles, both aliphatic and aromatic, are employed and afford the corresponding amides in good to excellent yields. Finally, mechanistic studies are performed to gain insight into both catalytic cycles.
A Versatile and practical solvating agent for enantioselective recognition and NMR analysis of protected amines
Iwaniuk, Daniel P.,Wolf, Christian
supporting information; experimental part, p. 6724 - 6727 (2010/12/19)
The 3,5-dinitrobenzoyl-derived 1-naphthylethyl amide 3 is an attractive CSA for NMR analysis of protected amines. It is readily prepared in a single step and combines practical resolution of diastereomeric complexes due to signal sharpness and effective signal separation. Crystallographic analysis shows that 3 forms a chiral cleft that can selectively bind one enantiomer of a substrate through hydrogen bonding, π-π stacking, and CH/π interactions. The enantioselective complex formation causes strong upfield shifts in the 1H NMR spectrum even in the presence of only 5 mol % of 3.
NEW CHIRAL STATIONARY PHASES FOR CHROMATOGRAPHY BASED ON AROMATIC ALLYL AMINES
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Page/Page column 16-17, (2009/10/22)
New chiral stationary phases (CSPs) based on chiral selectors covalently bound on a solid support were prepared. Chiral selectors were obtained from enantiomerically pure aromatic amines and 3,5-dinitrobenzoic acid and then linked to the support surface through the allylic double bond. Such obtained materials allow enantioseparation of racemates or enantiomerically enriched compounds. These chiral stationary phases can be used as fillings in chromatographic columns for enantiomer separation of naproxen type drugs and other similar non-steroidal anti-inflammatory drugs (NSAID) by means of high performance liquid chromatography on both the analytical and preparative scale.
New sterically driven mode for generation of helical chirality
Ueki, Hisanori,Soloshonok, Vadim A.
supporting information; experimental part, p. 1797 - 1800 (2009/09/05)
The presented results and the available literature data convincingly suggest that there Is a new sterlcally driven mechanism for the formation of supramolecular hellclty In the solid state. This mechanism requires the presence of sterlcally bulky groups, such as tert-butyl, for which the spiral arrangement In uninterrupted hydrogen-bonding chains, serving as an axis for helical structure and maximizing the repulsive stereochemical Interactions, provide for the most efficient, spatially economical accommodation of these groups In a crystallographlc unit cell.
Processes for producing 7-isoindolinequinolonecarboxylic derivatives and intermediates therefor, salts of 7-isoindolinequinolonecarboxylic acids, hydrates thereof, and composition containing the same as active ingredient
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Referential example II-1, (2010/11/29)
This invention relates to processes for producing a 7-isoindoline-quinolonecarboxylic acid derivative represented by the general formula [1] which is useful as an antibacterial agent, and an intermediate thereof: wherein R1represents a hydrogen atom or a carboxyl-protecting group; R2represents a substituted or unsubstituted alkyl, alkenyl, cycloalkyl, aryl or heterocyclic group; R3represents at least one group selected from hydrogen atom, halogen atoms, substituted or unsubstituted alkyl, alkenyl, cycloalkyl, aryl, alkoxy or alkylthio groups, nitro group, cyano group, acyl groups, protected or unprotected hydroxyl groups and protected or unprotected or substituted or unsubstituted amino groups; R4represents at least one group selected from hydrogen atom, halogen atoms, substituted or unsubstituted alkyl, alkenyl, cycloalkyl, aralkyl, aryl, alkoxy or alkylthio groups, protected or unprotected hydroxyl or imino groups, protected or unprotected or substituted or unsubstituted amino groups, alkylidene groups, oxo group and groups each forming a cycloalkane group together with the carbon atom to which R4bonds; R5represents a hydrogen atom, an amino-protecting group, a substituted or unsubstituted alkyl, cycloalkyl, alkylsulfonyl, arylsulfonyl, acyl or aryl group; R6represents a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl, alkoxy or alkylthio group, a protected or unprotected hydroxyl or amino group or a nitro group; and A represents CH or C—R7in which R7represents a halogen atom, a substituted or unsubstituted alkyl, alkoxy or alkylthio group or a protected or unprotected hydroxyl group, and to a salt of a 7-isoindoline-quinolonecarboxylic acid represented by the general formula [1], a hydrate thereof and a composition comprising them as an active ingredient.
Preparation of esters and amides from carboxylic acids by activation with dialkyl phosphite-carbon tetrachloride mixture
Jaszay, Zsuzsa M.,Petnehazy, Imre,Toke, Laszlo
, p. 2761 - 2768 (2007/10/03)
A simple one pot phase transfer catalytic method is described for the synthesis of carboxylic amides and esters from carboxylic acids and amines or alcohols, respectively. For the activation of the carboxylic acids 'in situ' generated phosphoric acid diester chlorides were applied.
Asymmetric synthesis of β-hydroxy sulfones by reduction of chiral β-keto sulfones
Bernabeu, M. Carmen,Bonete, Pedro,Caturla, Francisco,Chinchilla, Rafael,Najera, Carmen
, p. 2475 - 2478 (2007/10/03)
Chiral β-keto sulfones 3 have been prepared from enantiomerically pure sulfinic acids 2 derived from (R)- and (S)-methylbenzylamine. Enantiospecific reduction of these ketosulfones 3 can be achieved using different hydrides affording β-hydroxy sulfones. O
Recoverable Chiral Sulfoxides for Asymmetric Synthesis: Preparation, Regeneration and Application to the Asymmetric Aldol Reaction
Butlin, Roger J.,Linney, Ian D.,Critcher, Douglas J.,Mahon, Mary F.,Molloy, Kieran C.,Wills, Martin
, p. 1581 - 1590 (2007/10/02)
The synthesis of a novel source of chiral sulfoxide and its application to the control of asymmetric aldol reactions is described.The sulfoxide precursor S(S)R-(+)-cis-4 may be recycled and thus affords a considerable advantage over currently a
Enantiomer Discrimination Arising from Solute-Solute Interactions in Partially Resolved Chloroform Solutions of Chiral Carboxamides
Jursic, Branko S.,Goldberg, Stanley I.
, p. 7172 - 7174 (2007/10/02)
Enantiomer discrimination is revealed in the 1H-NMR spectra of partially resolved samples of seven chiral carboxamides.Signal separation is temperature and concentration dependent, and it varies smoothly with enantiomer composition, being a maximum when t
Dependence of Ring Closure Stereoselectivity on the Nature of the Leaving Group: Application to the Synthesis of a New Class of Chiral Sulfoxide for the Control of Asymmetric Aldol Reactions
Wills, Martin,Butlin, Roger J.,Linney, Ian D.,Gibson, Richard W.
, p. 3383 - 3385 (2007/10/02)
Enantiomerically pure cyclic sulfinamide (S(S)R)-(+)-1 , which has application to the control of asymmetric aldol reactions via a derived sulfoxide, has been prepared in diastereoisomerically pure form from the sulfinic acid (R)-(-)-5 using thionyl chloride-4-dimethylaminopyridine (DMAP); replacement of DMAP with pyridine or triethylamine gave both diastereoisomers of 1 in low diastereoisomeric excess.