20218-55-7Relevant academic research and scientific papers
1-(1-Naphthyl)ethylamine and Derivatives thereof as Chiral Modifiers in the Enantioselective Hydrogenation of Ethyl Pyruvate over Pt-Alumina
Heinz, Thomas,Wang, Guozhi,Pfaltz, Andreas,Minder, Bruno,Schuerch, Markus,et al.
, p. 1421 - 1422 (1995)
Catalytic quantities of (R)- or (S)-1-(1-naphthyl)ethylamine induce up to 82percent e.e. in the hydrogenation of ethyl pyruvate over Pt-alumina, the actual modifier responsible for enantioselection being the secondary amine resulting from imine formation
Enantioselective hydrogenation of ethyl pyruvate over Pt/alumina modified by (R)-1-(1-naphthyl)ethylamine derivatives
Minder,Schueren,Mallat,Baiker,Heinz,Pfaltz
, p. 261 - 268 (1996)
A new chiral modifier, (R)-1-(1-naphthyl)ethylamine, has been tested in the enantioselective hydrogenation of ethyl pyruvate to ethyl lactate over 5 wt% Pt/Al2O3. The influence of catalyst (2-28 g liter-1) and modifier concentration (0-20 mM), temperature (282-333 K), pressure (1-75 bar), and solvents was studied in a slurry reactor. The 82% enantiomeric excess (ee) at full conversion was achieved in acetic acid after optimizing the reaction parameters. Under mild conditions the new modifier affords ee's better than that achieved with cinchona alkaloids. A drop in ee at pressures higher than 10 bar and temperatures above 288 K is attributed to partial hydrogenation of the naphthalene ring, which hinders the adsorption of the modifier parallel to a flat Pt surface. Maximum rate acceleration by a factor of 12, compared to the racemic reaction, was observed after thermal treatment of the catalyst in flowing hydrogen at 673 K, followed by aerobic treatment at 273-298 K in acetic acid. It is shown that naphthylethylamine is only a precursor of the actual modifier, which is a secondary amine formed in situ from naphthylethylamine and ethyl pyruvate by condensation to the corresponding imine and subsequent reduction of the C=N bond. Several other derivatives of naphthylethylamine were prepared by reductive alkylation and tested as modifiers. The results indicate that the presence of an oxygen function such as a hydroxy or methoxy group, as in previously used modifiers, is not an indispensable requirement for obtaining high ee in the hydrogenation of α-ketoesters.
Stereogenic Lock in 1-Naphthylethanamine Complexes for Catalyst and Auxiliary Design: Structural and Reactivity Analysis for Cycloiridated Pseudotetrahedral Complexes
Chen, Houguang Jeremy,Hong Xiang Teo, Ronald,Li, Yongxin,Pullarkat, Sumod A.,Leung, Pak-Hing
supporting information, p. 99 - 106 (2018/01/17)
A series of optically active pseudo-tetrahedral five-membered cyclometalated 1-naphthylethanamine iridium(III) complexes were prepared and characterized to analyze the efficacy of the stereogenic conformational lock in both solid and solution phases. The synthesis of the iridacycles was diastereoselective, and the compounds were found to be conformationally rigid. In comparison to its phenyl derivative, the structural lock prevented oxidation of the amine moiety within the five-membered organometallic ring during its synthesis. With up to three stereogenic centers in one of the naphthalene complexes, the stereochemistry of the metallacycle remained stable to both thermal and chemical changes. In terms of catalytic performance, the complexes displayed excellent activity for the asymmetric hydrogen transfer reaction, albeit with modest enantioselectivities.
Chiral derivatives of Butenafine and Terbinafine: synthesis and antifungal activity
Fuglseth, Erik,Otterholt, Eli,H?gmoen, Hanne,Sundby, Eirik,Charnock, Colin,Hoff, B?rd Helge
experimental part, p. 9807 - 9813 (2010/02/27)
Two series of allylamines/benzylamines have been synthesised and evaluated for their antifungal activity towards Cryptococcus neoformans. All compounds are chiral derivatives of Butenafine and Terbinafine, having additional substituents at the carbon conn
Diastereoselective carbozincation of propargylic amines
Rezaei, Hadi,Marek, Ilan,Normant, Jean F
, p. 2477 - 2483 (2007/10/03)
The carbometalation of propargylic amines derived from methylbenzylamine takes place with good 1,3-diastereoselection in the presence of Lewis acids.
Optically active imidazolidin-2-one derivatives
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, (2008/06/13)
A novel optically active cis-4,5-disubstituted imidazolidin-2-one derivative of the formula: STR1 wherein R1 is a C1 -C4 alkyl group or benzyl and R2 is a chiral aralkyl group optionally having at least one of C1 -C4 alkyl, C1 -C4 alkoxy and hydroxyl groups is produced asymmetrically by the reaction of 1,3-dibenzyl-cis-4,5-dicarboxy-imidazolidin-2-one or its anhydride with an optically active secondary amine of the formula: STR2 wherein R1 and R2 are each as defined above and is transformed into the lactone of 1,3-dibenzyl-cis-4-carboxy-5-hydroxymethyl-imidazolidin-2-one, which is a key intermediate in the synthesis of d-biotin.
