Measurement of the dimerization equilibrium constants of enantiomers

Renato Baciocchi, Gianmarco Zenoni, Massimiliano Valentini, Marco Mazzotti, Massimo Morbidelli

Research output: Contribution to journalArticle

29 Citations (Scopus)

Abstract

The formation of homochiral and heterochiral dimers in solutions of enantiomers causes a number of remarkable phenomena, such as the enantiomeric enrichment of nonracemic mixtures on achiral chromatographic columns when chiral monomers and dimers exhibit different retention behavior. In this work, such effects on optical rotation and UV absorbance are analyzed theoretically and experimentally. In particular, it is demonstrated how optical rotation measurements can be used to estimate the dimerization equilibrium constants. It is shown how significant this is for polarimeter calibration, as well as for the determination of enantiomer concentrations in process streams, when optical rotation and UV absorbance measurements are combined. All experimental measurements refer to the enantiomers of the chiral 2,2'-dihydroxy-1,1'-binaphthyl in chloroform, at a temperature of 23 °C. The measured values of its dimerization equilibrium constants are 1.3 ± 0.5 and 3.1 ± 1.0 L/mol for the formation of homochiral and of heterochiral dimers, respectively.

Original languageEnglish
Pages (from-to)10461-10469
Number of pages9
JournalJournal of Physical Chemistry A
Volume106
Issue number43
DOIs
Publication statusPublished - Oct 31 2002

Fingerprint

Optical rotation
Dimerization
Enantiomers
enantiomers
Equilibrium constants
dimerization
Dimers
dimers
Polarimeters
Chloroform
polarimeters
Monomers
chloroform
Calibration
monomers
causes
estimates
Temperature
temperature

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry

Cite this

Measurement of the dimerization equilibrium constants of enantiomers. / Baciocchi, Renato; Zenoni, Gianmarco; Valentini, Massimiliano; Mazzotti, Marco; Morbidelli, Massimo.

In: Journal of Physical Chemistry A, Vol. 106, No. 43, 31.10.2002, p. 10461-10469.

Research output: Contribution to journalArticle

Baciocchi, R, Zenoni, G, Valentini, M, Mazzotti, M & Morbidelli, M 2002, 'Measurement of the dimerization equilibrium constants of enantiomers', Journal of Physical Chemistry A, vol. 106, no. 43, pp. 10461-10469. https://doi.org/10.1021/jp020352n
Baciocchi, Renato ; Zenoni, Gianmarco ; Valentini, Massimiliano ; Mazzotti, Marco ; Morbidelli, Massimo. / Measurement of the dimerization equilibrium constants of enantiomers. In: Journal of Physical Chemistry A. 2002 ; Vol. 106, No. 43. pp. 10461-10469.
@article{efedbf89eec84c56a47782f75f106157,
title = "Measurement of the dimerization equilibrium constants of enantiomers",
abstract = "The formation of homochiral and heterochiral dimers in solutions of enantiomers causes a number of remarkable phenomena, such as the enantiomeric enrichment of nonracemic mixtures on achiral chromatographic columns when chiral monomers and dimers exhibit different retention behavior. In this work, such effects on optical rotation and UV absorbance are analyzed theoretically and experimentally. In particular, it is demonstrated how optical rotation measurements can be used to estimate the dimerization equilibrium constants. It is shown how significant this is for polarimeter calibration, as well as for the determination of enantiomer concentrations in process streams, when optical rotation and UV absorbance measurements are combined. All experimental measurements refer to the enantiomers of the chiral 2,2'-dihydroxy-1,1'-binaphthyl in chloroform, at a temperature of 23 °C. The measured values of its dimerization equilibrium constants are 1.3 ± 0.5 and 3.1 ± 1.0 L/mol for the formation of homochiral and of heterochiral dimers, respectively.",
author = "Renato Baciocchi and Gianmarco Zenoni and Massimiliano Valentini and Marco Mazzotti and Massimo Morbidelli",
year = "2002",
month = "10",
day = "31",
doi = "10.1021/jp020352n",
language = "English",
volume = "106",
pages = "10461--10469",
journal = "Journal of Physical Chemistry A",
issn = "1089-5639",
publisher = "American Chemical Society",
number = "43",

}

TY - JOUR

T1 - Measurement of the dimerization equilibrium constants of enantiomers

AU - Baciocchi, Renato

AU - Zenoni, Gianmarco

AU - Valentini, Massimiliano

AU - Mazzotti, Marco

AU - Morbidelli, Massimo

PY - 2002/10/31

Y1 - 2002/10/31

N2 - The formation of homochiral and heterochiral dimers in solutions of enantiomers causes a number of remarkable phenomena, such as the enantiomeric enrichment of nonracemic mixtures on achiral chromatographic columns when chiral monomers and dimers exhibit different retention behavior. In this work, such effects on optical rotation and UV absorbance are analyzed theoretically and experimentally. In particular, it is demonstrated how optical rotation measurements can be used to estimate the dimerization equilibrium constants. It is shown how significant this is for polarimeter calibration, as well as for the determination of enantiomer concentrations in process streams, when optical rotation and UV absorbance measurements are combined. All experimental measurements refer to the enantiomers of the chiral 2,2'-dihydroxy-1,1'-binaphthyl in chloroform, at a temperature of 23 °C. The measured values of its dimerization equilibrium constants are 1.3 ± 0.5 and 3.1 ± 1.0 L/mol for the formation of homochiral and of heterochiral dimers, respectively.

AB - The formation of homochiral and heterochiral dimers in solutions of enantiomers causes a number of remarkable phenomena, such as the enantiomeric enrichment of nonracemic mixtures on achiral chromatographic columns when chiral monomers and dimers exhibit different retention behavior. In this work, such effects on optical rotation and UV absorbance are analyzed theoretically and experimentally. In particular, it is demonstrated how optical rotation measurements can be used to estimate the dimerization equilibrium constants. It is shown how significant this is for polarimeter calibration, as well as for the determination of enantiomer concentrations in process streams, when optical rotation and UV absorbance measurements are combined. All experimental measurements refer to the enantiomers of the chiral 2,2'-dihydroxy-1,1'-binaphthyl in chloroform, at a temperature of 23 °C. The measured values of its dimerization equilibrium constants are 1.3 ± 0.5 and 3.1 ± 1.0 L/mol for the formation of homochiral and of heterochiral dimers, respectively.

UR - http://www.scopus.com/inward/record.url?scp=0037206755&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0037206755&partnerID=8YFLogxK

U2 - 10.1021/jp020352n

DO - 10.1021/jp020352n

M3 - Article

AN - SCOPUS:0037206755

VL - 106

SP - 10461

EP - 10469

JO - Journal of Physical Chemistry A

JF - Journal of Physical Chemistry A

SN - 1089-5639

IS - 43

ER -