Multivariate Regression with Substituent Shift Increments. III. 2,5-Disubstituted Furans

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Title:Multivariate Regression with Substituent Shift Increments. III. 2,5-Disubstituted Furans
Creators:
Holík, Miroslav
Friedl, Zdeněk
Marchalín, Štefan
Journal or Publication Title:
Collection of Czechoslovak Chemical Communications, 64, 10, pp. 1696-1708
Uncontrolled Keywords:Linear regression, Furans, <sup>13</sup>C NMR substituent chemical shifts, Assignment of <sup>13</sup>C NMR signals, Substituent shift increments, Substituent effects, NMR spectroscopy

Abstract

Six series of 2-X-5-Y-substituted furans were used for multivariate regression of <sup>13</sup>C NMR chemical shifts with four substituent shift increments (SSI). Some of these series were measured in CDCl<sub>3</sub> and DMSO-<i>d</i><sub>6</sub> on different spectrometers to exclude possible sources of deviation from the general trends. Program ASSIGN was written for visual and numerical estimation of correct assignment of <sup>13</sup>C NMR spectra in the series of derivatives. Multivariate regression proved that the corresponding position in benzenes and furans are not affected by the substituents in the same way: in 2-X-5-Y-substituted furans, the "<i>ortho</i>" position requires correction for the different bond order, the "<i>meta</i>" <sup>13</sup>C chemical shift is probably affected by change in diamagnetic contribution of the Y group, and "<i>para</i>" position behaves like another "<i>ortho</i>" position in the molecule. <p>

Title:Multivariate Regression with Substituent Shift Increments. III. 2,5-Disubstituted Furans
Creators:
Holík, Miroslav
Friedl, Zdeněk
Marchalín, Štefan
Uncontrolled Keywords:Linear regression, Furans, <sup>13</sup>C NMR substituent chemical shifts, Assignment of <sup>13</sup>C NMR signals, Substituent shift increments, Substituent effects, NMR spectroscopy
Divisions:Life and Chemical Sciences > Institute of Organic Chemistry and Biochemistry > Collection of Czechoslovak Chemical Communications
Journal or Publication Title:Collection of Czechoslovak Chemical Communications
Volume:64
Number:10
Page Range:pp. 1696-1708
ISSN:0010-0765
E-ISSN:1212-6950
Publisher:Institute of Organic Chemistry and Biochemistry
Related URLs:
URLURL Type
http://dx.doi.org/10.1135/cccc19991696UNSPECIFIED
ID Code:1589
Item Type:Article
Deposited On:06 Feb 2009 17:10
Last Modified:06 Feb 2009 16:10

Citation

Holík, Miroslav; Friedl, Zdeněk; Marchalín, Štefan (1999) Multivariate Regression with Substituent Shift Increments. III. 2,5-Disubstituted Furans. Collection of Czechoslovak Chemical Communications, 64 (10). pp. 1696-1708. ISSN 0010-0765

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