Diethyl 2,4-dinitrophenyl phosphate

Zinc complexes of the cyclen ([12]aneN4 = 1,4,7,10-tetraazacyclododecane) ligand have been extensively studied in terms of phosphate ester hydrolysis reactivity. For example, a proposed binuclear Zn(II) hydroxide complex of cyclen was reported to enhance the rate of hydrolysis of ethyl(2,4-dinitrophenyl)-methylphosphonate and diethyl(2,4-dinitrophenyl) phosphate.223,224 It should be noted that the nuclearity of the zinc-cyclen complex in solution was not conclusively identified in this work. 

The products of phosphorylation of imidazole (IMZ) by two activated phosphate diesters, BDNPP (72) and ethyl 2,4-dinitrophenyl phosphate (EtDNPP) (73) and the related triester, diethyl 2,4-dinitrophenyl phosphate (Et2DNPP) (74) are stable enough... 

The phosphorylation of imidazole by diethyl 2,4-dinitrophenyl phosphate (74) was discussed in the earlier sub-section on phosphate diesters. ... 

Attack occurred at the C( 1) aromatic carbon as well as the P=0 group for reactions of diethyl 2,4-dinitrophenyl phosphate with phenoxides, secondary alicyclic amines, and pyridines. The absence of breaks in the Br0nsted-type plots for attack at P=0 pointed to a concerted mechanism, but values in the range 0.32-0.71 for attack at the aromatic C(l) were consistent with stepwise mechanisms and formation of Meisenheimer complexes." ... 

Di-3,5-dinitrophenyl phosphate is hydrolyzed to orthophosphate, and benzyl 3,5-dinitrophenyl phosphate to benzyl phosphate [26], upon UV irradiation. Also, adenosine has been phosphorylated with di-3,5-dinitrophenyl phosphorochloridate and the two protecting groups removed by irradiation to yield adenosine 5 -phosphate. The photo-initiated hydrolysis is accompanied by almost complete P—0, as opposed to C—O, bond fission. Similarly 3-nitrophenol has been used as a protecting group for the synthesis of the highly reactive Pi, Pi-diethyl pyrophosphate [27] (Fig. 6.10). In this case the group was removed by irradiation in 0.05 M-KOH solution. 

K. Yoshida, Y. Kurono, Y. Mori, K. Ikeda, Esterase-Like Activity of Human Serum Albumin. V. Reaction with 2,4-Dinitrophenyl Diethyl Phosphate , Chem. Pharm. Bull. 1985, 33, 4995-5001. 

The reactivity of zinc complexes supported by a variety of tridentate amine donor ligands (Fig. 44) with diphenyl 4-nitrophenyl phosphate in 20% (v/v) acetonitrile-water, and with 2,4-dinitrophenyl diethyl phosphate in 1 % (v/v) in methanol-water, has been investigated. 5 For the former reaction, the second-order rate constant for the hydrolysis of 2,4-dinitrophenyl diethyl phosphate correlates linearly with the —AH value for the formation of the [(ligand)Zn(OH2)]2 + complex from free chelate ligand and aqueous zinc ion. This indicates that in this series of complexes, faster hydrolysis of 2,4-dinitrophenyl diethyl phosphate corresponds to weaker chelate... 

Mononuclear zinc complexes of A, A /,A ///-tris(3-aminopropyl)amine ligands having either hydrogen atoms or methyl groups as the substituents on the coordinating nitrogen atoms exhibit slight catalytic activity for the hydrolysis of the phosphotriester 2,4-dinitrophenyl diethyl phosphate.233 A zinc hydroxide complex is proposed as the reactive species that promotes phosphotriester hydrolysis. 

The reactions of p-nitrophenyl toluenesulfonate (147) and 2,4-dinitrophenyl toluene-sulfonate (148) with a wide range of oximate ions (p/fa = 7-13) in 10% aqueous ethanol at 25 °C have been studied. For oximate ions with p/fa > 9.0, the reactivity of the oximes tends toward that of alcoholate ions and their a-effect disappears [as was also shown with /7-nitrophenyl diethyl phosphate (128) and ethyl jo-nitrophenyl ethylphosphonate (129)]. The reason for this is the unfavourable solvation effects of... 

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