2007
Partially O-Alkylated thiacalix[4]arenes: Synthesis, molecular and crystal structures, conformational behavior
DVOŘÁKOVÁ, Hana, Jan LANG, Jiří VLACH, Jan SÝKORA, Michal ČAJAN et. al.Základní údaje
Originální název
Partially O-Alkylated thiacalix[4]arenes: Synthesis, molecular and crystal structures, conformational behavior
Název česky
Parciálně O-alkylované thiacalix[4]areny: Syntéza, molekulové a krystalové struktury, konformační chování
Autoři
DVOŘÁKOVÁ, Hana (203 Česká republika, garant), Jan LANG (203 Česká republika), Jiří VLACH (203 Česká republika), Jan SÝKORA (203 Česká republika), Michal ČAJAN (203 Česká republika), Michal HIML (203 Česká republika), Michaela POJAROVÁ (203 Česká republika), Ivan STIBOR (203 Česká republika) a Pavel LHOTÁK (203 Česká republika)
Vydání
Journal of Organic Chemistry, Columbus, OH, USA, the American Chemical Society, 2007, 0022-3263
Další údaje
Jazyk
angličtina
Typ výsledku
Článek v odborném periodiku
Obor
10401 Organic chemistry
Stát vydavatele
Spojené státy
Utajení
není předmětem státního či obchodního tajemství
Impakt faktor
Impact factor: 3.959
Kód RIV
RIV/00216224:14310/07:00019544
Organizační jednotka
Přírodovědecká fakulta
UT WoS
000249371200010
Klíčová slova anglicky
ALTERNATE CONFORMATION; CONE INTERCONVERSION; INFINITE CHANNELS; SOLID-STATE; X-RAY; COMPLEXATION; THIACALIXARENES; CONFORMERS; H-1-NMR; NMR
Štítky
Příznaky
Recenzováno
Změněno: 7. 1. 2008 09:37, doc. RNDr. Michal Čajan, Ph.D.
V originále
NMR spectroscopy, X-ray diffraction analysis, and quantum chemical calculations were used for conformational behavior study of partially alkylated thiacalix[4]arenes bearing methyl (1), ethyl (2), or propyl (3) groups at the lower rim. The conformational properties are governed by two basic effects: (i) stabilization by intramolecular hydrogen bonds, and (ii) sterical requirements of the alkoxy groups at the lower rim. While the monosubstituted derivatives la and 3a adopt the cone conformation in solution, distally disubstituted compounds 1b, 1'b, 2b, 2'b, 3b, and 3'b exhibit several. interesting conformational features. They prefer pinched cone conformation in solution, and, except for 3'b, they form also 1,2-alternate conformation, which is flexible and undergoes rather fast transition between two identical structures. The crystal structures of the compounds 1b, 2b, 2'b, and 3b revealed yet quite rare 1,2-alternate conformation forming molecular channels held together by pi-pi interactions. Different channels-with hexagonal symmetry, 0.26 nm wide-are formed in the crystal structure of the pinched cone conformation of 3b. An uncommon hydrogen bonding pattern was found in dimethoxy and dipropoxy derivatives 1'b and 3'b that adopt distorted cone conformations in crystal. Trialkoxy-substituted compounds 1c and 3c adopt the partial cone conformation in solution. A higher mobility of methyl derivative 1c enables also existence of the cone conformer.
Česky
NMR spectroscopy, X-ray diffraction analysis, and quantum chemical calculations were used for conformational behavior study of partially alkylated thiacalix[4]arenes bearing methyl (1), ethyl (2), or propyl (3) groups at the lower rim. The conformational properties are governed by two basic effects: (i) stabilization by intramolecular hydrogen bonds, and (ii) sterical requirements of the alkoxy groups at the lower rim. While the monosubstituted derivatives la and 3a adopt the cone conformation in solution, distally disubstituted compounds 1b, 1'b, 2b, 2'b, 3b, and 3'b exhibit several. interesting conformational features. They prefer pinched cone conformation in solution, and, except for 3'b, they form also 1,2-alternate conformation, which is flexible and undergoes rather fast transition between two identical structures. The crystal structures of the compounds 1b, 2b, 2'b, and 3b revealed yet quite rare 1,2-alternate conformation forming molecular channels held together by pi-pi interactions. Different channels-with hexagonal symmetry, 0.26 nm wide-are formed in the crystal structure of the pinched cone conformation of 3b. An uncommon hydrogen bonding pattern was found in dimethoxy and dipropoxy derivatives 1'b and 3'b that adopt distorted cone conformations in crystal. Trialkoxy-substituted compounds 1c and 3c adopt the partial cone conformation in solution. A higher mobility of methyl derivative 1c enables also existence of the cone conformer.
Návaznosti
| IAA400200503, projekt VaV |
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| MSM0021622413, záměr |
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