Catalysts are substances that increase the reaction rate of a chemical reaction without being consumed in the process. Introducing a new discovery about 499-40-1, Name is (2R,3S,4R,5R)-2,3,4,5-Tetrahydroxy-6-(((2S,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)hexanal, SDS of cas: 499-40-1.
Reactions of CuF2, CuCl2 ? 2H2O and CuBr2 with 2,2?-dipyridylamine (HDPA) in water at room temperature using Cu:HDPA = 2:1 mol yield [Cu(HDPA)(H2O) 2F]F ? 3H2O (1), Cu(HDPA)Cl2 (2) and Cu(HDPA)Br2 (3) respectively. The structures of 2 and 3 are isostructural in spacegroup C2 with cell dimensions; for 2, a = 14.702(8), b = 7.726(2), c = 4.829(6) A, beta = 96.68(8) and for 3, a = 14.2934(8), b = 7.9057(6), c = 5.1982(5) A, beta = 94.049(7). In the X-ray crystal structure, the complex 1 is found to contain tapes of water pentamers. Our DFT calculations at the B3LYP/LanL2DZ level show that the reaction Cu(HDPA)X2 + 2H2O = [Cu(HDPA)(H 2O)2X]X is most exothermic in the gas phase when X – = F-, i.e., the tendency of water uptake is maximum for Cu(HDPA)F2. It seems that the exothermicities of the aquations of Cu(HDPA)Cl2 and Cu(HDPA)Br2 are not sufficient to stabilise the type of ribbons of water observed in 1 and consequently water is eschewed when X- = Cl- or Br-. Cu(2,2?-dipyridylamine)X2 takes up water to produce ribbons of water pentamer, as shown in the accompanied picture (red: O atom of a solvent water molecule), only when X- is F- but not when it Cl- or Br-. The results are rationalised by means of DFT calculations at the B3LYP/LanL2DZ level. [Figure not available: see fulltext.]
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.SDS of cas: 499-40-1, you can also check out more blogs about499-40-1
Reference：
Tetrahydropyran – Wikipedia,
Tetrahydropyran – an overview | ScienceDirect Topics