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The ionic complex [PtCl3(C2H4)]^-[(S,S)-(PhMeCH)2NH2]⁺ containing a chiral secondary amine is a new and versatile chiral derivatizing agent (CDA) for the determination of the enantiomeric composition of several unsaturated compounds including simple olefins:  the diastereoisomeric mixtures arising from the exchange of ethylene by the unsaturated analytes are easily detected by ¹⁹⁵Pt NMR spectroscopy.

The development of 2-[(R)-1-(9-anthryl)ethylamino]-4-chloro-6-methoxy-1,3,5-triazine, 2-[(R)-1-(9-anthryl)ethylamino]-4-chloro-6-[(R)-1-(1-naphthyl)ethylamino]-1,3,5-triazine and 2-[(R)-1-(9-anthryl)ethylamino]-4,6-bis-[(R)-1-(1-naphthyl)ethylamino]-1,3,5-triazine as chiral solvating agents (CSAs) for the determination of the enantiomeric composition of derivatized and underivatized chiral compounds is presented. The comparison between the efficiency of these chiral auxiliaries with the corresponding 1-(1-naphthyl)ethylamino substituted s-triazine derivatives is also discussed.

2-Hexylamino-4-[(S)-1-(1-naphthyl)ethylamino]-6-L-valyl-L-valyl-L-valine isopropylester-1,3,5-triazine (1), a molecule characterized by two different chiral selectors, and 2-hexylamino-4,6-bis-L-valyl-L-valyl-L-valine isopropylester-1,3,5-triazine (2) and 2-ethoxy-4-hexylamino-6-[(S)-1-(1-naphthyl) ethylamino]-1,3,5-triazine (3), systems in which a single kind of chiral selector is present, have been prepared. The enantiodiscriminating ability in solution of the three compounds toward the N-3,5-dinitrobenzoyl derivatives of 1-phenylethylamine (4) or valine methylester (5) has been investigated by ¹H nuclear magnetic resonance (NMR) spectroscopy: 1 shows an improved versatility, relative to 2 and 3, as a chiral solvating agent for NMR spectroscopy. On the basis of the indications obtained, the usefulness of 2-chloro-4-[(S)-1-(1-naphthyl)ethylamino]-6-L-val-L-val-L-valine isopropylester-1,3,5-triazine (1a), a direct precursor of 1, as chiral solvating agent for the determination by NMR of the enantiomeric compositions of derivatives of amines, amino alcohols, amino acids, and carboxyl acids bearing a 3,5-dinitrophenyl moiety, has been demonstrated. Chirality 9:113–121, 1997. © 1997 Wiley-Liss, Inc.

2‐Hexylamino‐4‐[(S)‐1‐(1‐naphthyl)ethylamino]‐6‐L‐valyl‐L‐valyl‐L‐valine isopropylester‐1,3,5‐triazine (1), a molecule characterized by two different chiral selectors, and 2‐hexylamino‐4,6‐bis‐L‐valyl‐L‐valyl‐L‐valine isopropylester‐1,3,5‐triazine (2) and 2‐ethoxy‐4‐hexylamino‐6‐[(S)‐1‐(1‐naphthyl) ethylamino]‐1,3,5‐triazine (3), systems in which a single kind of chiral selector is present, have been prepared. The enantiodiscriminating ability in solution of the three compounds toward the N‐3,5‐dinitrobenzoyl derivatives of 1‐phenylethylamine (4) or valine methylester (5) has been investigated by 1H nuclear magnetic resonance (NMR) spectroscopy: 1 shows an improved versatility, relative to 2 and 3, as a chiral solvating agent for NMR spectroscopy. On the basis of the indications obtained, the usefulness of 2‐chloro‐4‐[(S)‐1‐(1‐naphthyl)ethylamino]‐6‐L‐val‐L‐val‐L‐valine isopropylester‐1,3,5‐triazine (1a), a direct precursor of 1, as chiral solvating agent for the determination by NMR of the enantiomeric compositions of derivatives of amines, amino alcohols, amino acids, and carboxyl acids bearing a 3,5‐dinitrophenyl moiety, has been demonstrated. Chirality 9:113–121, 1997. © 1997 Wiley‐Liss, Inc.

The ionic CDA [PtCl3(C2H4)]^-[(S,S)-(1-NpMeCH)2NH2]⁺ produces, on exchange of its coordinated ethylene by chiral trisubstituted allenes, diastereoisomeric mixtures originating distinct ¹⁹⁵Pt NMR resonances for the complexed enantiomers, thus allowing the determination of the enantiomeric purity. A reproducible correlation between relative positions of platinum signals due to the complexed enantiomers and their absolute configuration has been found.

Rhodium-catalyzed deuterioformylation of 1,1-diphenylethene at partial substrate conversion (15 and 34%) at 100 °C and 100 atm (CO/D2 = 1:1) gives, in addition to the expected 3,3-diphenylpropanal-1,3-d2, the monodeuterated olefin 1,1-diphenylethene-2-d1 and the labeled normal aldehyde arising from this substrate. The above compounds have been detected by ²H NMR analysis of the crude reaction mixtures. These findings demonstrate that a tertiary alkyl−rhodium intermediate is formed, under hydroformylation conditions, in a larger amount than the normal isomer, but it undergoes β-hydride elimination only without formation of the branched aldehyde.

The optically active Grignard reagent (II), which is available by a conventional straightforward elaboration starting from (‐)‐menthone (I), reacts with prochiral ketones such as (III) to give exclusively reduction products, e.g. (IV); contrary to what is generally observed with aliphatic alkyl butyl Grignards, no addition products are additionally formed.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.