Conformation of eight-membered benzoannulated lactams by combined NMR and DFT studies

2012
journal article
article
dc.abstract.enThe title compounds were synthesized, and their structure and conformational behavior in solution (NMR and DFT), in the gas phase (DFT), and, for some of them, in the solid state (X-ray) were investigated. The variable -temperature NMR spectra were employed to determine the conformational equilibria and the activation energy of the conformational changes of the eight-membered ring. The coalescence effects are assigned to racemization of the chiral ground- state conformation with a ring inversion barrier in the range of 38-100 kJ mol$^{-1}$ depending on the relative setting of the two strong conformational constraints: benzoannulation and the amide function. The second conformational process, interconversion between two different conformers, in the molecules of benzo[c]azocin-3-one, benzo[d]azocin-2-one, and benzo[d]azocin-4-one was observed. The natures of the conformers observed in solution were elucidated by analysis of experimental and calculated NMR data. The present results are discussed in conjunction with previous experimental and theoretical data on (Z,Z)-cyclooctadienes and their benzo analogues.pl
dc.affiliationWydział Chemii : Zakład Krystalochemii i Krystalofizykipl
dc.affiliationWydział Chemii : Zakład Chemii Organicznejpl
dc.contributor.authorWitosińska, Agnieszkapl
dc.contributor.authorMusielak, Bogdan - 126144 pl
dc.contributor.authorSerda, Paweł - 131829 pl
dc.contributor.authorOwińska, Mariapl
dc.contributor.authorRys, Barbara - 131753 pl
dc.date.accessioned2015-03-12T07:44:27Z
dc.date.available2015-03-12T07:44:27Z
dc.date.issued2012pl
dc.description.number21pl
dc.description.physical9784-9794pl
dc.description.volume77pl
dc.identifier.doi10.1021/jo301859hpl
dc.identifier.eissn1520-6904pl
dc.identifier.issn0022-3263pl
dc.identifier.urihttp://ruj.uj.edu.pl/xmlui/handle/item/3743
dc.languageengpl
dc.language.containerengpl
dc.rightsDodaję tylko opis bibliograficzny*
dc.rights.licencebez licencji
dc.rights.uri*
dc.subtypeArticlepl
dc.titleConformation of eight-membered benzoannulated lactams by combined NMR and DFT studiespl
dc.title.journalThe Journal of Organic Chemistrypl
dc.typeJournalArticlepl
dspace.entity.typePublication
dc.abstract.enpl
The title compounds were synthesized, and their structure and conformational behavior in solution (NMR and DFT), in the gas phase (DFT), and, for some of them, in the solid state (X-ray) were investigated. The variable -temperature NMR spectra were employed to determine the conformational equilibria and the activation energy of the conformational changes of the eight-membered ring. The coalescence effects are assigned to racemization of the chiral ground- state conformation with a ring inversion barrier in the range of 38-100 kJ mol$^{-1}$ depending on the relative setting of the two strong conformational constraints: benzoannulation and the amide function. The second conformational process, interconversion between two different conformers, in the molecules of benzo[c]azocin-3-one, benzo[d]azocin-2-one, and benzo[d]azocin-4-one was observed. The natures of the conformers observed in solution were elucidated by analysis of experimental and calculated NMR data. The present results are discussed in conjunction with previous experimental and theoretical data on (Z,Z)-cyclooctadienes and their benzo analogues.
dc.affiliationpl
Wydział Chemii : Zakład Krystalochemii i Krystalofizyki
dc.affiliationpl
Wydział Chemii : Zakład Chemii Organicznej
dc.contributor.authorpl
Witosińska, Agnieszka
dc.contributor.authorpl
Musielak, Bogdan - 126144
dc.contributor.authorpl
Serda, Paweł - 131829
dc.contributor.authorpl
Owińska, Maria
dc.contributor.authorpl
Rys, Barbara - 131753
dc.date.accessioned
2015-03-12T07:44:27Z
dc.date.available
2015-03-12T07:44:27Z
dc.date.issuedpl
2012
dc.description.numberpl
21
dc.description.physicalpl
9784-9794
dc.description.volumepl
77
dc.identifier.doipl
10.1021/jo301859h
dc.identifier.eissnpl
1520-6904
dc.identifier.issnpl
0022-3263
dc.identifier.uri
http://ruj.uj.edu.pl/xmlui/handle/item/3743
dc.languagepl
eng
dc.language.containerpl
eng
dc.rights*
Dodaję tylko opis bibliograficzny
dc.rights.licence
bez licencji
dc.rights.uri*
dc.subtypepl
Article
dc.titlepl
Conformation of eight-membered benzoannulated lactams by combined NMR and DFT studies
dc.title.journalpl
The Journal of Organic Chemistry
dc.typepl
JournalArticle
dspace.entity.type
Publication

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