MP2 and DFT calculations have been carried out for [n]circulenes for n=3 to 20 in order to predict the strain energy and topology of these cyclically condensed aromatic systems. To synthesise [4]circulene (2), 1,5,7,8-tetrakis(bromomethyl)biphenylene (14) was prepared from the corresponding tetramethyl derivative (8) and subjected to various dehalogenation reactions; all attempts to obtain [2.2]biphenylenophane (7) as a precursor for 2 by this route failed. Treatment of 14 with sodium sulfide furnished the thiaphanes 16 and 17, thermal and photochemical desulfurization of which also failed to provide 7. In a second approach [2.2]paracyclophane was converted to the pseudo-geminal dithiol 23, which was subsequently bridged to the thiaphanes 22 and 24. On flash vacuum pyrolysis at 800 degrees C these were converted exclusively into phenanthrene (30). An approach to dehydrochlorinate the commercial product PARYLENE C to the tetrahydro[4]circulene 7 led only to polymerisation. The X-ray structures of the intermediates 8, 14, 17, 23, 24, 26, and 35 are reported.
Zusammenfassung
Es wird bei 102 Hunden eine einmalige Schrägsenkung mit der Senkrechtsenkung verglichen. Dabei wird festgestellt, daß der 7‐, 10‐ und 20‐Minutenwert der Schrägsenkung dem 1‐, 2‐ und 24‐Stundenwert der Senkrechtsenkung entspricht. Zu diesen Untersuchungen wurde Kobers Blutsenkungs‐Meßapparat „Pronto” verwendet, der bei einfacher Konstruktion ein hygienisch völlig einwandfreies Füllen der Westergrenröhrchen mit dem zu untersuchenden Zitratblut erlaubt.
Summary
The red cell sedimentation rate in the dog in Westergren tubes inclined at 60°
In 102 dogs the sedimentation rate in inclined tubes was compared with that in vertical tubes. The values obtained after 7, 10 and 20 minutes by oblique sedimentation corresponded to those after 1, 2 and 24 hours, respectively, with vertical tubes. For these measurements the simply constructed “Pronto” apparatus of Kobers was used and provided a hygienic and ready method of filling the Westergren tubes with the citrated blood.
Résumé
La vitesse de sédimentation des hématies chez le chien dans un tube de Westergren incliné à 60°
L'auteur à comparé une fois chez 102 chiens la vitesse de sédimentation dans un tube oblique à la vitesse de sédimentation dans un tube vertical. Il put ainsi constater que les valeurs obtenues au bout de 7, 10 et 20 minutes dans la sédimentation oblique correspondaient aux valeurs obtenues au bout de 1, 2 et 24 heures dans la sédimentation verticale. Pour ces recherches, il se servit de l'appareil à mesurer la vitesse de sédimentation de Kober «Pronto», qui de construction simple, permet le remplissage absolument hygiénique des tumbes de Westergren avec le sang citraté à examiner.
Resumen
Sobre la prueba de la eritrosedimentación en el perro en tubitos de Westergren inclinados en un ángulo de 60°
En 102 perros se compara una sola sedimentación inclinada con la sedimentación vertical. De esta forma se comprueba que el valor de los 7, 10 y 20 minutos de la sedimentación inclinada corresponden al valor de las 1, 2 y 24 horas de la sedimentación vertical. Para estas investigaciones se utilizó el aparato „Pronto” de Kober para medir la velocidad de sedimentación sanguínea, que con una construcción simple permite el llenado higiénico totalmente irrecusable de los tubitos de Westergren con la sangre citratada a investigar.
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