Detailed Information on Publication Record
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.Basic information
Original name
Partially O-Alkylated thiacalix[4]arenes: Synthesis, molecular and crystal structures, conformational behavior
Name in Czech
Parciálně O-alkylované thiacalix[4]areny: Syntéza, molekulové a krystalové struktury, konformační chování
Authors
DVOŘÁKOVÁ, Hana (203 Czech Republic, guarantor), Jan LANG (203 Czech Republic), Jiří VLACH (203 Czech Republic), Jan SÝKORA (203 Czech Republic), Michal ČAJAN (203 Czech Republic), Michal HIML (203 Czech Republic), Michaela POJAROVÁ (203 Czech Republic), Ivan STIBOR (203 Czech Republic) and Pavel LHOTÁK (203 Czech Republic)
Edition
Journal of Organic Chemistry, Columbus, OH, USA, the American Chemical Society, 2007, 0022-3263
Other information
Language
English
Type of outcome
Článek v odborném periodiku
Field of Study
10401 Organic chemistry
Country of publisher
United States of America
Confidentiality degree
není předmětem státního či obchodního tajemství
Impact factor
Impact factor: 3.959
RIV identification code
RIV/00216224:14310/07:00019544
Organization unit
Faculty of Science
UT WoS
000249371200010
Keywords in English
ALTERNATE CONFORMATION; CONE INTERCONVERSION; INFINITE CHANNELS; SOLID-STATE; X-RAY; COMPLEXATION; THIACALIXARENES; CONFORMERS; H-1-NMR; NMR
Tags
Tags
Reviewed
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.
In Czech
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.
Links
| IAA400200503, research and development project |
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| MSM0021622413, plan (intention) |
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