The crystal of p-tert-butylthiacalix[4]arene (2) includes mono-, di-, and trimethylamines from their respective aqueous solutions to give 1:1 (host/guest) inclusion crystals. In competitive inclusion of these three amines, dimethylamine is selectively included. X-ray crystallographic analysis of the inclusion crystals of dimethylamine and trimethylamine reveals that the amines are included by forming salts with the calixarene (H 4 L). In the inclusion crystal of dimethylamine, two dimethylammonium ions and two water molecules form an aggregate, which is interposed between two calix anions (H 3 L − ) arranged in a tail-to-tail manner to construct an exo complex. In the inclusion crystal of trimethylamine, however, a trimethylammonium ion is included in the cavity of the calix anion to form an endo complex. In competitive inclusion of dimethylamine and trimethylamine, the guest selectivity can be switched by changing the polarity of solvent; dimethylamine and trimethylamine are selectively included from low-(32.4 ≤ ε ≤ 65.9) and high-permittivity solvents (88.9 ≤ ε ≤ 132.6), respectively. Mechanistic studies reveal that the inclusions of dimethylamine and trimethylamine are favored under kinetic and thermodynamic control, respectively.
A crystal of the
exocavity complex of p-tert-butylthiacalix[4]arene (2) with diethylamine
(2·Et2NH) includes alkanes that cannot
be included in a crystal
of compound 2 alone and produces two types of inclusion
crystals. X-ray crystallographic analysis of inclusion crystals 2·Et2NH·(hexane)0.5 and 2·(Et2NH)1.5·(heptane)0.5·H2O, which were chosen as representatives
of the two types, reveals that hexane and heptane are captured in
a space surrounded by four self-inclusion dimers of the exocavity
complex and in a capsule constructed by two exocavity complexes, respectively.
The crystal of 2·Et2NH selectively includes
hexane, heptane, and octane from mixtures with their branched isomers.
Porous
materials, which can capture a specific compound from a
hard-to-separate molecular mixture, are strongly desired for practical
separation and purification processes. Aiming to develop such materials,
we have investigated the performance of our original host compounds,
[3,3′-thiobis(5-tert-butyl-2-hydroxybenzene)-1,1′-diyl]diacetic
acid (2) and its monopropyl ester (3), in
discriminating among regio- or stereoisomers of three groups of amines,
2-, 3-, and 4-methylpyridine, 2-, 6-, and 8-methylquinoline, and cis- and trans-4-cyclohexanamine. Diacid 2 selectively included 4-methylpyridine in hexane and 3-methylpyridine
in toluene in competitive inclusion among the three regioisomers.
Mechanistic studies revealed that the inclusions of 3- and 4-methylpyridine
are favored under kinetic and thermodynamic control, respectively.
Solvent-dependent switching in guest selectivity was also observed
in competitive inclusion among the methylquinoline isomers with diacid 2, whereas trans-4-methylcyclohexanamine
was selectively included over the cis-isomer by monoester 3, as well as diacid 2, regardless of the solvent
employed. X-ray crystallographic analysis of the resulting inclusion
crystals suggests that the wide guest scope of the host compounds
originates from their flexible ability to form complexes with amines.
A 38-year-old woman was admitted to our hospital on Nov. '85 because of mild bleeding tendency. There was past history of malignant lynphoma of the stomach at age 34. Then she had gastrectomy and splenectomy with subsequent X-ray therapy.Coagulation tests on admission revealed ; platelet count 259,000/pl; bleeding time (Duke), 8.5min.; whole blood clotting time, prothrombin time, partial thromboplastin time were normal. There was the abnormality of platelet function to aggregate in response to ADP, epinephrine and collagen, whereas ristocetin-induced agglutination was normal (Fig.
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