TY - JOUR
T1 - Conformational studies of dibenzo-16-crown-5 lariat ethers
AU - Bartsch, Richard A.
AU - Kim, Jong Seung
AU - Olsher, Uriel
AU - Purkiss, David M.
N1 - Funding Information:
This research was supported by the Division of Chemical Sciences of the Office of Basic Energy Sciences of the U.S. Department of Energy (Grant DE-FG03-94ER14416).
PY - 1996
Y1 - 1996
N2 - Conformations of sym-(R)(OR')dibenzo-16-crown-5 compounds with R = decyl and R' = H, CH3, CH2CO2H, and CH2CO2CH3, as well as R = alkyl, fluoroalkyl, alkenyl, and alkynyl and R' = CH2CO2H, in solution have been probed by NMR spectroscopy. The difference in chemical shifts of the diastereotopic hydrogens for the methylene groups adjacent to the geminally substituted ring carbon is utilized to assess the ease of inversion of the three-carbon bridges. For lariat ethers with R = C10H21, the chemical shift difference is much larger when R' = CH2CO2H and CH2CO2CH3 than H and CH3. In non-hydrogen bonding solvents, the chemical shift difference for lariat ethers with R = C10H21 is much larger when R' = CH2CO2H than CH2CO2CH3 which demonstrates intramolecular hydrogen bonding of the carboxylic acid-containing side arm with a crown ether oxygen.
AB - Conformations of sym-(R)(OR')dibenzo-16-crown-5 compounds with R = decyl and R' = H, CH3, CH2CO2H, and CH2CO2CH3, as well as R = alkyl, fluoroalkyl, alkenyl, and alkynyl and R' = CH2CO2H, in solution have been probed by NMR spectroscopy. The difference in chemical shifts of the diastereotopic hydrogens for the methylene groups adjacent to the geminally substituted ring carbon is utilized to assess the ease of inversion of the three-carbon bridges. For lariat ethers with R = C10H21, the chemical shift difference is much larger when R' = CH2CO2H and CH2CO2CH3 than H and CH3. In non-hydrogen bonding solvents, the chemical shift difference for lariat ethers with R = C10H21 is much larger when R' = CH2CO2H than CH2CO2CH3 which demonstrates intramolecular hydrogen bonding of the carboxylic acid-containing side arm with a crown ether oxygen.
UR - http://www.scopus.com/inward/record.url?scp=0002152376&partnerID=8YFLogxK
U2 - 10.1080/10610279608032551
DO - 10.1080/10610279608032551
M3 - Article
AN - SCOPUS:0002152376
SN - 1061-0278
VL - 6
SP - 327
EP - 331
JO - Supramolecular Chemistry
JF - Supramolecular Chemistry
IS - 3-4
ER -