The reaction rate of a catalyzed reaction is faster than the reaction rate of the uncatalyzed reaction at the same temperature.33100-27-5, Name is 1,4,7,10,13-Pentaoxacyclopentadecane, molecular formula is C10H20O5. In a Article£¬once mentioned of 33100-27-5, Product Details of 33100-27-5
A high temperature reversible phase transition in a supramolecular complex of 15-crown-5 with tetraphenylboron sodium
A supramolecular crystal, [Na(15-crown-5)][BPh4] (1), (15-crown-5 = 1,4,7,10,13-pentaoxacyclopentadecane, NaBPh4 = sodium tetraphenylboron), has been obtained by mixing the ethanol solution of 15-crown-5 and NaBPh4 in the molar ratio of 1:1. The crystal structure was determined at 293 K, revealing that two [Na(15-crown-5)]+ cations form a supramolecular dimer via sharing one side-edge of coordination pentagonal pyramids; also, there are significant H-bonding interactions between anions and supramolecularly dimeric cations. Differential scanning calorimetry (DSC) showed that 1 undergoes a reversible first-order phase transition at ca. 391 K (Tc) upon heating, with a thermal hysteresis of 19 K. DeltaH and DeltaS were estimated to be 6.9 kJ mol-1 and 17.7 J mol-1 K-1, respectively, in the heating run. The variable-temperature powder X-ray diffraction and dielectric spectra were collected, and both disclosed no significant difference between the low- and high-temperature phases. These results suggest that the phase transition is an ordered-disordered type, which probably involves the change of anion configuration.
Note that a catalyst decreases the activation energy for both the forward and the reverse reactions and hence accelerates both the forward and the reverse reactions.Product Details of 33100-27-5, you can also check out more blogs about33100-27-5
Reference£º
Chiral Catalysts,
Chiral catalysts – SlideShare