ISSN:
1572-9001
Schlagwort(e):
Triphenylmethane
;
structure
;
energetics
;
molecular propellers
;
conformations
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Chemie und Pharmazie
Notizen:
Abstract The motivation for this study was the interesting, and contrasting, reported crystallization modes of triphenylmethane and triphenylsilane, the former said to crystallize as a conglomerate [Riche and Pascard-Billy,Acta Crystallog. B 1974,30, 1874], whereas the latter was reported to crystallize as a racemate [Allemand and Gerdi,Cryst. Struct. Commun. 1979,8, 927]. As we show in what follows, we had planned to justify these observations via molecular mechanics and semiempirical (AM1) calculations. However, in the process of doing some geometrical calculations unavailable in the original, we found that it was impossible for the reported structure [Riche and Pascard-Billy,op. cit.] to be correct. Therefore, we redetermined the structure and found that triphenylmethane also crystallizes as a racemate. The compound was recrystallized from toluene and its structure was solved in space groupPna21 (No. 33). The cell constants area=25.593(14),b=14.804(19),c=7.521(15) å;V=2849.5(6) å3,d(MW=244.32 g mol−1;z=8)=1.139 g cm−3. A total of 2183 independent reflections were collected over the range 4
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF02252970
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