Variation of the stereoparameters for description geometry of calix[4]arenes - more suitable solution for "flat systems"

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F18%3A10376996" target="_blank" >RIV/00216208:11310/18:10376996 - isvavai.cz</a>

Result on the web

<a href="http://chemistry-vestnik.ksu.kz/apart/2018-90-2/3.pdf" target="_blank" >http://chemistry-vestnik.ksu.kz/apart/2018-90-2/3.pdf</a>

DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Variation of the stereoparameters for description geometry of calix[4]arenes - more suitable solution for "flat systems"

Original language description

This article deals with a variation of previously introduced parameters alpha, beta, and delta which were used to describing the all possible conformations of these compounds, cone, partial cone, 1,2- and 1,3-alternate conformers of methylene- and heteroatom-bridged calix[4] arenes. Usefulness of these parameters alpha, beta, delta have been already demonstrated, but, it seems, to be more suitable to do any variations them for flat systems. The background for the parameters a, , d lies in the representation of the scale of the angles of the calix[4] arene rings towards the reference plane. The original scale 0 degrees - 360 degrees for these angles depicts very well the differences between the calix[4 ] arene conformations but has two significant disadvantages. The first one is the discontinuity of the scale. The angles alpha(i) range approximately from 0 degrees to 110 degrees and from 250 degrees to 360 degrees because of the sterical hindrance that would occur should the calixarene phenyl ring enter the cavity. The second disadvantage is the discontinuity at the point alpha(i) = 0 degrees, it means the case of flat systems. These flat systems are usually the &apos;transitions states&apos; between the calixarene conformations and cannot be observed using parameters alpha, beta, delta. To eliminate the difficulties in describing the &apos;transition states&apos; between the calix[4] arene conformations caused by the discontinuities of the original scale, the new scale should be introduced. New parameters alpha &apos;, beta &apos;,delta &apos; were introduced by subtracting 360 degrees for each &apos;negative&apos; ring present in the structure (one for partial cone conformers, two for 1,2- and 1,3-alternate conformers); after the parameters alpha, beta, delta are calculated.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10402 - Inorganic and nuclear chemistry

Project

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Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2018

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Bulletin of Karaganda State University, Series chemistry

ISSN

2518-718X

e-ISSN

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Volume of the periodical

neuveden

Issue of the periodical within the volume

90

Country of publishing house

KZ - KAZAKSTAN

Number of pages

8

Pages from-to

23-30

UT code for WoS article

000438647100003

EID of the result in the Scopus database

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