The reaction rate of a catalyzed reaction is faster than the reaction rate of the uncatalyzed reaction at the same temperature.61363-56-2, Name is 2H-Pyran-3,5(4H,6H)-dione, molecular formula is C5H6O3. In a Article£¬once mentioned of 61363-56-2, Recommanded Product: 2H-Pyran-3,5(4H,6H)-dione
Green’ synthesis of 2-substituted 6-hydroxy-[3H]-pyrimidin-4-ones and 4,6-dichloropyrimidines: Improved strategies and mechanistic study
An improved route to 2-substituted 6-hydroxy-[3H]-pyrimidin-4-ones 4 and to 2-substituted 4,6-dichloropyrimidines 5 is reported. Without using highly toxic reactants, compounds 4 can be prepared conveniently in a one pot synthesis on a one mol scale with average yields up to 80%. 4,6-Dichloropyrimidines 5, which are usually prepared in small quantities, are synthesized with average yields of 80%, using up to 80g of starting material. The mechanism of the chlorination of 4 is investigated computationally for the first time. The results suggest that the chlorination with phosphoryl chloride occurs in an alternating phosphorylation-chlorination manner (pathway 1) which is preferred over a sequence which starts with two phosphorylations. The investigated 4,6-dichloropyrimidines described herein form strong complexes with dichlorophosphoric acid but weak complexes with hydrochloric acid (generated during workup). These latter complexes explain the necessity of using aqueous sodium carbonate during the working up. In order to prevent possible formation of pyrimidinium salts between intermediates or the final dichloropyrimidines and unreacted hydroxypyrimidone, the latter could be deactivated with a strong acid such as dichlorophosphoric acid, thus allowing chlorination but prohibiting salt formation. Because of its general applicability to all nitrogen heterocycle chlorinations with phosphoryl chloride, the proposed route to dichloropyrimidines without solvent or side products, using less toxic reactants, is of general synthetic interest.
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.Recommanded Product: 2H-Pyran-3,5(4H,6H)-dione, you can also check out more blogs about61363-56-2
Reference£º
Tetrahydropyran – Wikipedia,
Tetrahydropyran – an overview | ScienceDirect Topics