0000000000921774
AUTHOR
Oleg Kasyan
showing 3 related works from this author
Hydrogen-bonded dimers of a thiacalixarene substituted by carbamoylmethylphosphineoxide groups at the wide rim.
2006
A thiacalix[4]arene derivative bearing four carbamoylmethylphosphineoxide groups at the wide rim forms hydrogen-bonded, dimeric capsules with S8 symmetry in the crystalline state and in apolar solvents, where the inclusion of cationic guests could be proved by 1H NMR and ESI mass spectra.
Unusual conformations of 1,3-dialkoxythiacalix[4]arenes in the solid state
2006
The structures of three syn-1,3-dialkoxythiacalix[4]arenes with unusual conformations in the solid state are reported. The pinched cone conformation of syn-2 2 ,4 2 -dihydroxy-1 2 ,3 2 -bis-(prop-2-enyloxy)thiacalix[4]arene, C 30 H 24 O 4 S 4 , (3a), is stabilized by two intramolecular hydrogen bonds, remarkably formed from both OH groups to the same ether O atom. In syn-22,42-dihydroxy-1 5 ,2 5 ,3 5 ,4 5 -tetranitro-12,32-bis(prop-2-enyloxy)thiacalix[4]arene acetone disolvate, C 30 H 20 N 4 O 12 S 4 ·-2C 3 H 6 O, (3b1), the molecule is found in the 1,3-alternate conformation. The crystallographic C2 symmetry is due to a twofold rotation axis running through the centre of the calixarene rin…
Dimeric Capsules Formed by Tetra-CMPO Derivatives of (Thia)Calix[4]arenes
2010
Thiacalix[4]arene 2, calix[4]arene 3 a and its tetraether fixed in the cone conformation 3 b form homo- and heterodimeric capsules in apolar solvents, which are held together by a seam of NH⋅⋅⋅O=P hydrogen bonds between carbamoylmethyl phospine oxide functions attached to their wide rim. Their internal volume of ∼370 A3 requires the inclusion of a suitable guest. Although neutral molecules such as adamantane (derivatives) or tetraethylammonium cations form kinetically stable complexes (1H- and 31P-time scale), the included solvent is rapidly exchanged. The internal mobility of the included tetraethylammonium cation is distinctly higher (ΔG=42.5 and 49.7 kJ mol−1 for 3 a and 3 b) than that f…