Reaktionen zwischen und in Molekülkristallen

Abstract

Reaktionen in und zwischen Molekülkristallen, insbesondere mechanisch ausgelöste Umsetzungen, werden in diesem Kurzaufsatz diskutiert. Den Schwerpunkt bilden Prozesse innerhalb oder zwischen Festkörpern, die vor allem durch supramolekulare Wechselwirkungen gesteuert werden: Templatcycloadditionen, Bildung von Einschlussverbindungen, Reaktionen von Molekülkristallen mit Umorganisation nichtkovalenter Bindungen und Bildung von Komplexen und Koordinationsverbindungen. Lösungsmittelfreie mechanochemische Verfahren wie Mahlen und Kneten bieten sich als umweltschonende Methoden zur Synthese von molekularen und supramolekularen Feststoffen an.

Hydrogen Bonding and Dynamic Behaviour in Crystals and Polymorphs of Dicarboxylic–Diamine Adducts: A Comparison between NMR Parameters and X‐ray Diffraction Studies

“…[15][16][17][18] A key aspect of the studies on polymorphism is the possibility of preparing crystal forms by means of nonsolution methods, such as the solvent-free mechanochemical cogrinding of solids. [19][20][21][22] The acid-base adducts investigated in this paper have also been selected in view of the fact that the main supramolecular interaction that holds the building blocks together is the hydrogen bond, undoubtedly the interaction of choice in the majority of crystal engineering investigations with molecular components. [23][24][25][26][27][28][29] The nature and strength of hydrogen-bonding interactions are being investigated extensively due to the requirements of crystal engineering.…”

Screening for Inclusion Compounds and Systematic Construction of Three‐Component Solids by Liquid‐Assisted Grinding

“…The presence of heteroatoms does not seem to inhibit cocrystal formation (Table 1, entries 1-5, 11-13). The host also accommodates molecules that do not contain a sixmembered ring (Table 1, entries [11][12][13][14][15]. Consequently, the likelihood of a molecule to be incorporated in 1 seems to be determined largely by size.…”

“…[12] Notably, our group, and others, have reported that binary cocrystals can readily be constructed by grinding together individual components, either neat or in the presence of a small amount of a liquid phase (liquid-assisted grinding). [13,14] That the amounts of liquid involved in liquid-assisted grinding experiments are typically very small suggests that the solubilities of individual components are not decisive for cocrystal formation by grinding.…”

Spin Crossover versus Low‐Spin Behaviour Exhibited in 2D and 3D Supramolecular Isomers of [FeII(2,4‐bpt)2]⋅Guest

“…Crystal data of 1·Fe-Co at 240(2) K: C 24 H 16 Co 0.07 Fe 0.93 N 10 ; M r = 500.53 g mol À1 ; monoclinic; space group P2 1 /n; a = 8.9225 (7), b = 14.3864 (11), c = 9.1726(8) ; b = 104.619(3)8; V = 1139.30 (16) 3 ; Z = 2; 1 = 1.459 g cm À3 ; q max = 27.008; total data 5941; unique data 2260; m = 0.704 mm À1 ; 157 parameters; R 1 = 0.0492 for I ! 2s(I) and wR 2 = 0.1496 for all data.…”