Synthesis, Conformation, and Binding Properties of Resorcarene Tetrasulfonates. Asymmetric Reorganization of Pendant Sulfonyl Groups via Intramolecular SO- - -H−O Hydrogen Bonds
摘要:
The regioselective reaction of resorcarene octaols 1 with 4 equiv of arylsulfonyl chlorides and Et3N in MeCN gives in 30-60% yield the C-2v symmetrical tetrasulfonates 3. The mild electrophilic substitution (aminomethylation, bromination) of resorcarene tetrasulfonates 3 and tetraphosphates 2 takes place only in the 2-positions of unsubstituted resorcinol rings yielding distally disubstituted resorcarenes 4. The acylation of hydroxy groups in compounds 2 and 3 gives C-2v symmetrical octaesters 5 including large resorcarene tetracrown-ethers. In the minimized boat conformation of tetrasulfonates 3 the two unsubstituted resorcinol rings are vertical and the sulfonyl fragments are arranged in a C-2 symmetrical manner via intramolecular S=O- - -H-O hydrogen bonds. This structure is proved by NMR and IR spectroscopy. In the case of tetrasulfonate 3c the two enantiomeric conformations interconvert in CDCl3 with Delta G* = 11.6 kcal/mol. This is in agreement with the Delta E* value predicted by molecular mechanics in vacuo.
Synthesis, Conformation, and Binding Properties of Resorcarene Tetrasulfonates. Asymmetric Reorganization of Pendant Sulfonyl Groups via Intramolecular SO- - -H−O Hydrogen Bonds
摘要:
The regioselective reaction of resorcarene octaols 1 with 4 equiv of arylsulfonyl chlorides and Et3N in MeCN gives in 30-60% yield the C-2v symmetrical tetrasulfonates 3. The mild electrophilic substitution (aminomethylation, bromination) of resorcarene tetrasulfonates 3 and tetraphosphates 2 takes place only in the 2-positions of unsubstituted resorcinol rings yielding distally disubstituted resorcarenes 4. The acylation of hydroxy groups in compounds 2 and 3 gives C-2v symmetrical octaesters 5 including large resorcarene tetracrown-ethers. In the minimized boat conformation of tetrasulfonates 3 the two unsubstituted resorcinol rings are vertical and the sulfonyl fragments are arranged in a C-2 symmetrical manner via intramolecular S=O- - -H-O hydrogen bonds. This structure is proved by NMR and IR spectroscopy. In the case of tetrasulfonate 3c the two enantiomeric conformations interconvert in CDCl3 with Delta G* = 11.6 kcal/mol. This is in agreement with the Delta E* value predicted by molecular mechanics in vacuo.
作者:Oleg V. Lukin、Vladimir V. Pirozhenko、Alexander N. Shivanyuk
DOI:10.1016/0040-4039(95)01573-z
日期:1995.10
Selective acylation of calixresorcinalarene 1 has been performed. The reaction with mild acylating agents such as arylsulfanylchlorides leads to the tetrasubstituted compounds. Stereochemistry of the compounds obtained has been investigated in detail by means of H-1- and C-13-NMR.
o-Alkylation of C-2v-symmetrical resorcinarene tetraesters 2 with 2 equiv of 1,3-difluoro-4,6-dinitrobenzene readily affords conformationally rigid octanitro resorcinarene 3, which is a potential scaffold for the design of supramolecular structures.
Synthesis, Conformation, and Binding Properties of Resorcarene Tetrasulfonates. Asymmetric Reorganization of Pendant Sulfonyl Groups via Intramolecular SO- - -H−O Hydrogen Bonds
作者:Oleg Lukin、Alexander Shivanyuk、Vladimir V. Pirozhenko、Ivan F. Tsymbal、Vitaly I. Kalchenko
DOI:10.1021/jo981751a
日期:1998.12.1
The regioselective reaction of resorcarene octaols 1 with 4 equiv of arylsulfonyl chlorides and Et3N in MeCN gives in 30-60% yield the C-2v symmetrical tetrasulfonates 3. The mild electrophilic substitution (aminomethylation, bromination) of resorcarene tetrasulfonates 3 and tetraphosphates 2 takes place only in the 2-positions of unsubstituted resorcinol rings yielding distally disubstituted resorcarenes 4. The acylation of hydroxy groups in compounds 2 and 3 gives C-2v symmetrical octaesters 5 including large resorcarene tetracrown-ethers. In the minimized boat conformation of tetrasulfonates 3 the two unsubstituted resorcinol rings are vertical and the sulfonyl fragments are arranged in a C-2 symmetrical manner via intramolecular S=O- - -H-O hydrogen bonds. This structure is proved by NMR and IR spectroscopy. In the case of tetrasulfonate 3c the two enantiomeric conformations interconvert in CDCl3 with Delta G* = 11.6 kcal/mol. This is in agreement with the Delta E* value predicted by molecular mechanics in vacuo.