The proportionality constant is the rate constant for the particular unimolecular reaction. the reaction rate is directly proportional to the concentration of the reactant. I hope my blog about 1608-26-0 is helpful to your research., Synthetic Route of 1608-26-0
Synthetic Route of 1608-26-0, Catalysts are substances that increase the reaction rate of a chemical reaction without being consumed in the process. 1608-26-0, Name is Tris(dimethylamino)phosphine
, molecular formula is P[N(CH3)2]3. In a Article£¬once mentioned of 1608-26-0
Thio effects on the departure of the 3?-linked ribonucleoside from diribonucleoside 3?,3?-phosphorodithioate diesters and triribonucleoside 3?,3?,5?-phosphoromonothioate triesters: Implications for ribozyme catalysis
To provide a solid chemical basis for the mechanistic interpretations of the thio effects observed for large ribozymes, the cleavage of triribonucleoside 3?,3?,5?-phosphoromonothioate triesters and diribonucleoside 3?,3?-phosphorodithioate diesters has been studied. To elucidate the role of the neighboring hydroxy group of the departing 3?-linked nucleoside, hydrolysis of 2?,3?-O-methyleneadenosin-5?-yl bis[5?-O-methyluridin-3?-yl] phosphoromonothioate (1a) has been compared to the hydrolysis of 2?,3?-O-methyleneadenosin-5?-yl 5?-O-methyluridin-3?-yl 2?,5?-di-O-methyluridin- 3?-yl phosphoromonothioate (1b) and the hydrolysis of bis[uridin-3?- yl] phosphorodithioate (2a) to the hydrolysis of uridin-3?-yl 2?,5?-di-O-methyluridin-3?-yl phosphorodithioate (2b). The reactions have been followed by RP HPLC over a wide pH range. The phosphoromonothioate triesters 1a,b undergo two competing reactions: the starting material is cleaved to a mixture of 3?,3?- and 3?,5?-diesters, and isomerized to 2?,3?,5?- and 2?,2?,5?-triesters. With phosphorodithioate diesters 2a,b, hydroxide-ion-catalyzed cleavage of the P-O3? bond is the only reaction detected at pH > 6, but under more acidic conditions desulfurization starts to compete with the cleavage. The 3?,3?-diesters do not undergo isomerization. The hydroxide-ion-catalyzed cleavage reaction with both 1a and 2a is 27 times as fast as that compared with their 2?-O-methylated counterparts 1b and 2b. The hydroxide-ion-catalyzed isomerization of the 3?,3?,5?-triester to 2?,3?,5?- and 2?,2?,5?-triesters with 1a is 11 times as fast as that compared with 1b. These accelerations have been accounted for by stabilization of the anionic phosphorane intermediate by hydrogen bonding with the 2?-hydroxy function. Thio substitution of the nonbridging oxygens has an almost negligible influence on the cleavage of 3?,3?-diesters 2a,b, but the hydrolysis of phosphoromonothioate triesters 1a,b exhibits a sizable thio effect, kPO/kPS = 19. The effects of metal ions on the rate of the cleavage of diesters and triesters have been studied and discussed in terms of the suggested hydrogen-bond stabilization of the thiophosphorane intermediates derived from 1a and 2a.
The proportionality constant is the rate constant for the particular unimolecular reaction. the reaction rate is directly proportional to the concentration of the reactant. I hope my blog about 1608-26-0 is helpful to your research., Synthetic Route of 1608-26-0
Reference£º
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate