On the hydrolysis of dimethyl-H-phosphonate. An 18O-labelling and 31P-NMR study

Mitchell, Michael C.; Taylor, Roger; Kee, Terence P.

doi:10.1016/s0277-5387(97)00369-0

Cited by 18 publications

(15 citation statements)

References 65 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…13C and D). [147][148][149] Data related to the activity of these Cd(II) complexes is presented in Table 2.…”

Section: Dinuclear Cadmium Hydrolase Mimicsmentioning

confidence: 99%

“…31 P-chemical shifts are very sensitive to structural changes arising from an 18 O bound to the phosphorus instead of an 16 O; the signal arising from 18 O is thus shifted to lower frequency. [147][148][149] For complexes utilising a nucleophile arising from a coordinated aqua ligand in a 50 : 50 18 O- 16 O environment is it expected that the product of the hydrolysis reaction will be found with 50% 18 O incorporated from the nucleophile. [147][148][149] The observation in the 31 P spectrum of a splitting of the product peak into a doublet ( peak separation of approximately 0.02 ppm) thus reflecting the 16 O/ 18 O substitution suggests that for complexes such as for [Zn 2 (CH 3 L2)(CH 3 COO) 2 ](PF 6 ) and [Zn 2 (CH 3 HL1)(CH 3 COO)-(H 2 O)](PF 6 ) the nucleophile is a Zn(II) bound water/hydroxide from the solvent.…”

Section: Biomimetics Of Dinuclear Metallohydrolasesmentioning

confidence: 99%

See 1 more Smart Citation

Spectroscopic and mechanistic studies of dinuclear metallohydrolases and their biomimetic complexes

et al. 2014

View full text Add to dashboard Cite

An enhanced understanding of the metal ion binding and active site structural features of phosphoesterases such as the glycerophosphodiesterase from Enterobacter aerogenes (GpdQ), and the organophosphate degrading agent from Agrobacterium radiobacter (OpdA) have important consequences for potential applications. Coupled with investigations of the metalloenzymes, programs of study to synthesise and characterise model complexes based on these metalloenzymes can add to our understanding of structure and function of the enzymes themselves. This review summarises some of our work and illustrates the significance and contributions of model studies to knowledge in the area.

show abstract

“…13C and D). [147][148][149] Data related to the activity of these Cd(II) complexes is presented in Table 2.…”

Section: Dinuclear Cadmium Hydrolase Mimicsmentioning

confidence: 99%

Section: Biomimetics Of Dinuclear Metallohydrolasesmentioning

confidence: 99%

Spectroscopic and mechanistic studies of dinuclear metallohydrolases and their biomimetic complexes

et al. 2014

View full text Add to dashboard Cite

show abstract

“…(HO)P(OEt) 2 A and (HO)P(O)(OPh) 2 B were purchased from Sigma-Aldrich with 98 and 99% purities, respectively. Propargylic alcohols 1a , 6 1b , 6 1c , 6 1d , 6 1e , 19 and 1f (16) were prepared according to the literature procedures. Column chromatography and thin-layer chromatography were performed on silica gel (Kieselgel 60), using UV light and a phosphomolybdic acid dip to visualize the products.…”

Section: Experimental Sectionmentioning

confidence: 99%

Taming Brønsted Acid Reactivity: Nucleophilic Substitutions of Propargylic Alcohols with N-Nucleophiles Mediated by Phosphorus-Based Brønsted Acid Catalysts

Radtanajiravong

Díez‐González

2019

ACS Omega

View full text Add to dashboard Cite

The activity of diethyl phosphite and diphenyl phosphate in propargylation reactions with N-nucleophiles of varying basicity is presented. A careful choice of the reaction conditions minimized undesired rearrangements and arylation processes, typical side reactions with Brønsted acid catalysis. These systems are compatible with technical solvents and presence of air, and they are also applicable to C-, O-, and S-nucleophiles.

show abstract

“…The presence of two electrophilic sites on H ‐phosphonate diesters, as well as tautomerization creates an environment for facile substituent exchange at these compounds. It has previously been established that H ‐phosphonate diesters can undergo hydrolysis to yield H ‐phosphonate monoesters (primary hydrolysis) and H ‐phosphonic acid (secondary hydrolysis) in reactions under high concentrations of water (Scheme a, first and second equilibria, respectively) . Similarly, alcoholysis (also reported as transesterification) is possible under high concentrations of alcohol (Scheme b) .…”

Section: Introductionmentioning

confidence: 99%

Facile Substituent Exchange at H‐Phosphonate Diesters Limiting an Effective Synthesis of D‐Phosphonate Diesters

et al. 2019

View full text Add to dashboard Cite

Research on using H-phosphonate diesters to introduce phosphorus functionality into molecules and polymers, some of which have medicinal applications, has recently attracted a lot of attention. Deuterium labelling to yield the corresponding D-phosphonate diesters, although desirable in order to help with the mechanistic elucidation of reactions containing H-phosphonate diesters, has been demonstrated to be a challenge. Deuterium exchange at Hphosphonate diesters using D 2 O, MeOD and ND 2 Bn has shown competitive behavior with hydrolysis, alcoholysis and aminolysis reactions, respectively. This facile substituent exchange for the addition of D 2 O and MeOD can be attributed to the similar energy required to eliminate ROH or H 2 O (ROD or HOD, R = iPr, Et, Me) from a pentavalent P(V) intermediate which is generated from axial delivery of an OD or OR group from D 2 O and MeOD, respectively. The trend in reaction rate for the exchange processes follows the order of R = Me > Et > iPr in (RO) 2 P(O)H and also depends on the nucleophilicity of the incoming group. Attempted synthesis of D-phosphonate diesters directly from PCl 3 and alcohols or via lithiation reactions further demonstrated just how sensitive the H/D-scrambling process is. These results have implications for the general reactivity of H-phosphonate diesters towards water, alcohol, and amines and their potential to selectively undergo substitution at either P-OR or P-H. Moreover, insight into the mechanism(s) of selective deuterium exchange, for example to give D-phosphonate diesters via the direct exchange of D for H, was illuminated through this research. at 101 MHz and are given in parts per million relative to CDCl 3 (δ = 77.0 ppm). Chemical shifts for 31 P NMR spectra are recorded at 161.97 MHz and given relative to external 85% phosphoric acid (δ = 0 ppm). Data are represented as follows: chemical shift, multiplicity (app = apparent, br = broad, s = singlet, d = doublet, t = triplet, q = quartet, m = multiplet), coupling constants in Hertz (Hz), and integration.

show abstract

On the hydrolysis of dimethyl-H-phosphonate. An 18O-labelling and 31P-NMR study

Cited by 18 publications

References 65 publications

Spectroscopic and mechanistic studies of dinuclear metallohydrolases and their biomimetic complexes

Spectroscopic and mechanistic studies of dinuclear metallohydrolases and their biomimetic complexes

Taming Brønsted Acid Reactivity: Nucleophilic Substitutions of Propargylic Alcohols with N-Nucleophiles Mediated by Phosphorus-Based Brønsted Acid Catalysts

Facile Substituent Exchange at H‐Phosphonate Diesters Limiting an Effective Synthesis of D‐Phosphonate Diesters

Contact Info

Product

Resources

About