Enantiomer separations of secondary alkanols with little asymmetry by high-performance liquid chromatography on chiral columns

Toru, Takeshi; Aoyanagi, Naoki; Nishimura, Kazuhiko; Ando, Yasuhiro; Ota, Toru

doi:10.1016/0021-9673(93)87053-o

Cited by 4 publications

(2 citation statements)

References 4 publications

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“…Urea groups are frequently found in enzyme inhibitors and pseudopeptides . The reactivity of isocyanates with nucleophiles has been widely studied due to interest in production of urethanes and polyurethane, − alcohol content measurement, − and more recently for analysis of environmental micropollutants …”

Section: Introductionmentioning

confidence: 99%

Design, Execution, and Analysis of Time-Varying Experiments for Model Discrimination and Parameter Estimation in Microreactors

Schaber

Born

Jensen

et al. 2014

Org. Process Res. Dev.

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Time-varying, or dynamic, experiments can produce richer data sets than sequences of steady-state experiments using less material and time. A case study demonstrating this concept for microreactor experiments is presented. Beginning with five kinetic model candidates for the reaction of phenylisocyanate with t-butanol, an initial dynamic experiment showed that two of the five models gave a similar quality of fit to the experimental data, whereas the remaining three gave significantly poorer fits. Next an optimal experiment was designed to discriminate between the remaining two models. This drove the two models to differ significantly in quality, leaving a single model and a set of kinetic parameter values that adequately described the data. This method can be applied to future kinetic studies to reduce material use and experimental time while validating a dynamic model of the physics and chemical kinetics.

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Section: Introductionmentioning

confidence: 99%

Design, Execution, and Analysis of Time-Varying Experiments for Model Discrimination and Parameter Estimation in Microreactors

Schaber

Born

Jensen

et al. 2014

Org. Process Res. Dev.

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“…In general, it is very difficult to separate enantiomers or diastereomers composed of C, H, and O atoms by HPLC or gas chromatography (GC), especially in the case of aliphatic chain compounds. For example, Figure 2 shows the separation results of 4-octanol or 4-nonanol, reported to date: (a) a racemic 4-octanol 3,5-DNPU (3,5-dinitrophenylurethane) derivative was subjected to chiral HPLC at −20 °C, but the separation factor α remained low as α = 1.06 [14]; (b) separation of racemic 4-nonanol acetate was attempted by chiral GC, but this was not successful, α = 1.0~1.01 [15]; (c) racemic 4-octanol was esterified with a chiral acid yielding diastereomers, which were separated by HPLC (reversed phase) at −40 °C, but α remained low as α = 1.04 [16].…”

Section: Introductionmentioning

confidence: 99%

HPLC Separation of Diastereomers: Chiral Molecular Tools Useful for the Preparation of Enantiopure Compounds and Simultaneous Determination of Their Absolute Configurations

Harada

2016

Molecules

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Abstract:To obtain enantiopure compounds, the so-called chiral high performance liquid chromatography (HPLC) method, i.e., HPLC using a chiral stationary phase, is very useful, as reviewed in the present Special Issue. On the other hand, normal HPLC (on silica gel) separation of diastereomers is also useful for the preparation of enantiopure compounds and also for the simultaneous determination of their absolute configurations (ACs). The author and coworkers have developed some chiral molecular tools, e.g., camphorsultam dichlorophthalic acid (CSDP acid), 2-methoxy-2-(1-naphthyl)propionic acid (MαNP acid), and others suitable for this purpose. For example, a racemic alcohol is esterified with (S)-(+)-MαNP acid, yielding diastereomeric esters, which are easily separable by HPLC on silica gel. The ACs of the obtained enantiopure MαNP esters can be determined by the 1 H-NMR diamagnetic anisotropy method. In addition, MαNP or CSDP esters have a high probability of giving single crystals suitable for X-ray crystallography. From the X-ray Oak Ridge thermal ellipsoid plot (ORTEP) drawing, the AC of the alcohol part can be unambiguously determined because the AC of the acid part is already known. The hydrolysis of MαNP or CSDP esters yields enantiopure alcohols with the established ACs. The mechanism and application examples of these methods are explained.

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Reactivity of 3 isopropenyl-α,α-dimethyl-benzylisocyanate with amines, phenols, thiols and oximes in diluted aqueous–organic media: the water-promoted effect

Vandenabeele-Trambouze

Mion²,

Garrelly

et al. 2001

Advances in Environmental Research

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Enantiomer separations of secondary alkanols with little asymmetry by high-performance liquid chromatography on chiral columns

Cited by 4 publications

References 4 publications

Design, Execution, and Analysis of Time-Varying Experiments for Model Discrimination and Parameter Estimation in Microreactors

Design, Execution, and Analysis of Time-Varying Experiments for Model Discrimination and Parameter Estimation in Microreactors

HPLC Separation of Diastereomers: Chiral Molecular Tools Useful for the Preparation of Enantiopure Compounds and Simultaneous Determination of Their Absolute Configurations

Reactivity of 3 isopropenyl-α,α-dimethyl-benzylisocyanate with amines, phenols, thiols and oximes in diluted aqueous–organic media: the water-promoted effect

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