Isomerization solid state

R = Bu X = Br, R = Et, Pr, Bu X = I R = Et, Pr) can be prepared by solid state isomerization of the m-form at a temperature just below the melting point by comparison, complexes of trimethyl- and triphenylphosphine decompose without change. Isomerization of PtCl2(EtCN)2 has likewise been studied [131b],... 

Decomposition of frarcs-[Co(pn)2Cl2](H502)Cl2 [1138] is accompanied by some solid state isomerization to the cis form. Reported values of E, based on first-order behaviour, were 138 and 500 kJ mole 1 for decomposition and isomerization, respectively. The rate of isomerization in the... 

This distinction is, however, only practical. Several reaction types are not easily encompassed in the above description. For instance, Scheffer (see within this book) has provided ample examples of stereocontrolled solid-state reactions [11], while solid-state isomerizations have been studied by Coville and Levendis [12]. These processes can be explained with the reaction cavity concept, i.e. reactivity takes place in a constrained environment generated by the surrounding molecules. Relevant contributions to the field have also derived from the studies of Eckhardt [13] and those of Ohashi and collaborators [14]. 

Otsuka M, Ohtani H, Otsuka K, Kaneniwa N. Effect of humidity on solid-state isomerization of various kinds of lactose during grinding. J Pharm Pharmacol 1993 45 2-5. 

The aqueous solution isomerization of the [CoSCN(NH3>5] ion (spontaneous, OH catalyzed, and Ag catalyzed) is reviewed with emphasis being placed on competition by other species in solution (N CS, N3 , NO3, H2O). A detailed account is given of the solid state isomerization of frfl/w-[CoSCN(NH3)4( NH3)](N CS)2 where the first products of heating at 60 C are trans-CoNCS (40%, intramolecular), cw-CoN CS " (30%, lattice), and cw-CoS CN ... 

The presence of a chelate ring, in general, should increase the thermal stability of metal complexes towards decomposition through a decrease in kinetic lability. Such trends have been observed in, for example, the solid state isomerization of platinum(II) complexes containing monodentate triphenylphosphine and bidentate dppm ligands. A study thermally-... 

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