Rofaxane Compoimnds, IThe name rotaxanes is suggested for newly synthesized aggregates of the type 1 consisting of a macrocycle and a chain with bulky end groups. As a model compound 4-(11-hydroxyundecy1)-catechol (11) can be ketalized with 1,21-dichlorheneicosan-l I-one to the benzodioxole 12. From the catechol-diol 16 the diansa compound 25b is synthesized which is then converted to the prerotaxane t6b with N-acety1-2,4,6-tri-p-tolylaniline, the structure of which is confirmed by the mass spectrum. T h e cleavage of the ketal 26b with hydrobromic acid affords the prerotaxane 27 coupled via N only, which after dehydrogenation and hydrolysis gives the rotaxane 29. Reductive acetylation leads to the hexaacetate 30. The corresponding non-rotaxane-like components, the pentaacetate 54 and the 1 -acetyl-I -aza-cyclohexacosan-14-one, are clearly different on thin layer chromatography from the rotaxane 30 which appears as a single spot with several mobile phases. The identical i.r.-spectrum of the rotaxane compounds 30 and of an equimolar mixture of the components (Fig. I ) confirms the postulated structure.
Six years ago [2] we discussed some of the principles involved in the synthesis of catena compounds, a new class of substances consisting of rings, which are not chemically combined but which are held together like the links of a chain (I), and began some experimental work on such systems [2,3].As thereactions we envisaged were of s t a t i s t i c a l character, only very poor yields were to be expected. Our experimental results [3] were even more disappointing than expected although they gave valuable information about the behavior and morphology of long-chain and macrocyclic compounds in solution.On the other hand, Wussevmarz [4] claimed to have obtained yields of approximately 1 % (relative to the entire mixture isolated) using one of these methods. Later on he modified this statement to a claim [5] of having obtained by chromatography yields that were several powers of ten less than those previously reported, namely a few milligrams of an oil which was thought to be a catenane. The new principle of the d i r e c t e d synthesis which we have now applied proved successful. By steric control it avoids the extra-annular ring closures which always occur predominantly in statistical cyclization methods. [6] was converted into the dicarboxylic ester (3) by Wittig reaction with an excess of 10-methoxycarbonyldecylidenetriphenylphosphorane [7]. Hydrolysis gave the crystalline dicarboxylic acid (4) (m.p. 67-71 OC, after sintering) in 52 -58 % yield based on (2). Catalytic hydrogenation and esterification of ( 4 ) gave (5). Surprisingly, this ester could not be cyclized by the acyloin ring closure method of Hansley, Pvrlog, and StoN, but remained unchanged, whereas the dicarboxylic ester (6) of a hydroquinone ether was cyclized readily. 4,5-Dimethoxyisophthalaldehyde (2) ____ 0~1 1~The diester (5) was therefore reduced to the diol (7) with LiAIH4, and (7) was converted into the dinitrile (9) via the dibromide (8). The cyclic P-imino nitrile obtained from (
Auf Grund von Modelluntersuchungen wird erstmals die gezielte Synthese einer Catena-Verbindung (11) verwirklicht. Aus 11 werden die Catena-Verbindungen 12-14 dargestellt.Die I Rund UV-Spektren und das chromatographische Verhalten der Catena-Verbindungen und der sie aufbauenden makrocyclischen Partner werden verglichen und zusarnmen mit der Molekulargewichtsbestimmung zum Konstitutionsbeweis herangezogen.Die Synthese einer Diansa-Verbindung des 5-Amino-4.6-dipropyl-1.3-benzodioxols und ihre Aufspaltung in den aromatischen Kern und den Makroheterocyclus ~ bestehend aus den beiden Ketten des doppelhenkligen Systems mit dern Stickstoffatom ~ wurden schon friiher beschrieben3.4). Aufbauend auf Erfahrungen dieser Modelluntersuchungen war beabsichtigt, die intraanular verknupfte Triansa-Verbindung 6a darzustellen und sie anschlieRend durch Spalten der C -0 -und C-N-Bindungen zwischen dem aromatischen Kern mit der Polymethylenkette und dem Makroheterocyclus in eine Catena-Verbindung umzuwandeln L4).
Zur Synthese der Hantel 7 haben wir (Trity1thio)essigsaure-methylester (6) in Tetrahydrofuran rnit Lithium-diisopropylamid bei -20°C deprotoniert und anschlieDend mit
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