32586-82-6Relevant articles and documents
Radiolysis of Di- and Tri-methyl Phosphates in Oxygenated Aqueous Solution: a Model System for DNA Strand Breakage
Schuchmann, Man Nien,Sonntag, Clemens von
, p. 699 - 704 (1984)
In the radiolysis of aqueous solutions of trimethyl phosphate saturated with N2O-O2 the major products (G values in parentheses) are dimethyl hydrogen phosphate (6.4), formic acid (3.4), formaldehyde (1.7), hydrogen peroxyde (2.1), organic peroxide (0.5), and carbon monoxide (1.0).Oxygen is consumed (G 4.1).In the dimethyl phosphate (sodium salt) system the products and their G values are similar to those of the trimethyl phosphate system.Pulse radiolytic studies have shown that in trimethyl phosphate system the first formed peroxyl radicals react with each other to give a short lived tetraoxide (2k = 9 x 1E8 dm3 mol-1 s-1).This intermediate decays either by concerted mechanism or by fragmentation to form O2 and two oxyl radicals.Among other reactions these oxyl radicals undergo a 1,2-hydrogen shift, followed by a complex series of reactions.There are two processes that yield acids at longer reaction times.The faster process has been identified as the hydrolysis of formic dimethylphosphoric anhydride (k = 0.3 + 2.3 x 1E4 -> s-1).The slower process (k = 2 600 s-1) is only observed in basic solutions and has not yet been identified with certainity.The present findings are used as a model to assist in the interpretation of some aspects of DNA radiolysis.
Benzoyl methyl phosphate as an efficient reagent for the selective monobenzoylation of N-Bz-FTY720
Hikawa, Hidemasa,Hamada, Maiko,Yokoyama, Yuusaku,Azumaya, Isao
supporting information, p. 23131 - 23136 (2014/06/24)
A novel and efficient method for the selective monobenzoylation of N-Bz-FTY720 with benzoyl methyl phosphate (BMP) promoted by Zn(OAc)2 and Cs2CO3 was developed. Benzoyl methyl phosphate plays an important role as a biomimetic acylating agent for the monobenzoylation of 1,3-diols.
Dissociative solvolytic cleavage of methyl (ortho-Carboxymethyl)Aryl phosphate diesters mediated by Yb3+ in methanol gives a 10 12-fold rate acceleration attributable to leaving group assistance
Edwards, David R.,Neverov, Alexei A.,Brown, R. Stan
supporting information; experimental part, p. 368 - 377 (2009/06/28)
The Yb3+-catalyzed cleavage of a series of eight methyl aryl phosphates (2a-h) where the aryl groups all contain an ortho-methoxycarbonyl group was studied in acidic methanol from 1.34 ≤ spHs ≤ 3.34 at 25 °C. All substrates show saturation binding of the metal ion that is analyzed to provide a conditional binding constant (K)b for a 1:1 substrate/Yb3+ complex and catalytic rate constant (A cat) that varies between about 2 × 10-3 and 50 × 10-3 s-1 overthe range of substrates. Detailed analysis indicates that at very low c oncentration of Yb3+, 3 equiv of substrate are bound, and with increasing [Yb3+], the binding changes to a 1:1 complex which decomposes by a pathway independent of spHs over the range investigated. Control studies show that substrates without the o-methoxycarbonyl group still bind to the Yb 3+ with approximately the same strength as do the o-methoxycarbonyl containing substrates but have no observable reaction when bound. A Jaffe plot of the kcat vs substituent ?-values indicates that, during the catalyzed reactions of 2a-h, the phenoxy-O and C(O)OCH3 groups accommodate negative and positive charge respectively, the p phosphate and p c(o)OMe values being (1.84 ±0.11) and ( 0.85 ±0.14). For all these substrates, the final reaction products are dimethyl phosphate and the Yb3+ complex of the phenoxide. A study of the binding of the parent phenols to Yb3+ indicates that log(Kbind) = (0.84 ± 0.06)sspKa+ (3.4 ± 0.9), r2 = 0.9664 for phenols containing the o-methoxycarbonyl group; for those lacking that substituent log(Kb ind) = (0.96 ± 0.04)s spKa- (1.73 ± 0.4), (r2 = 0.99). For the catalyzed reacti on the βlg = -0.48, while the βeq = -0.95, leading to a Leffler parameter of α = 0.51. A mechanism is presented for the catalyzed reaction which is highly dissociative, having a transition state where the Yb3+ translocates during the cleavage reaction to assist the leaving group's departure with weak nucleophilic assistance by the solvent methanol. A comparison of the catalyzed rate of reaction with a computed rate of reaction attributable to solvent alone indicates that Yb3+ provides leaving group assistance on the order of 1012-fold, stabilizing the transition state for cleavage by some 16 kcal/mol.
