ChemInform Abstract: Heats of Reaction of Cyclic and Acyclic Phosphate and Phosphonate Esters. “Strain Discrepancy” and Steric Retardation.

The energies and heats of ion-molecule reactions have been calculated (MP4/6-31G**//6-31G** or better level) and compared with the experimental values obtained from the heats of formation. Two main types of reactions have been studied: (i) AHn + AHn+• ↔ AHn+1+ + AHn-1• (A = C to F and Si to Cl), (ii) AHn + BHm+• ↔ AHn+1+ + BHm-1• or AHn-1+• + BHm+1+ (A and B = C to F). In contrast to (i), processes of type (ii) permit easy differentiation between the proton transfer and hydrogen atom abstraction mechanisms. A third type of interaction involves reactions with radical anions (A = Li to F); comparison was made with analogous processes with radical cations. A brief comment is made about the influence of the level of computational sophistication on the energies and heats of reaction, as well as on the stabilization energy of a hydrogen bonded intermediate, a structure which is similar to that of the reaction products.

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Heats of reaction from self-consistent-field energies of closed-shell molecules

Journal of the American Chemical Society ◽

10.1021/ja01037a001 ◽

1969 ◽

Vol 91 (9) ◽

pp. 2189-2198 ◽

Cited By ~ 81

Author(s):

Lawrence C. Snyder ◽

Harold Basch

Keyword(s):

Closed Shell ◽

Consistent Field ◽

Self Consistent ◽

Heats Of Reaction ◽

Self Consistent Field

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A Sustainable Improvement of ω-Bromoalkylphosphonates Synthesis to Access Novel KuQuinones

Organics ◽

10.3390/org2020010 ◽

2021 ◽

Vol 2 (2) ◽

pp. 107-117

Author(s):

Mattia Forchetta ◽

Valeria Conte ◽

Giulia Fiorani ◽

Pierluca Galloni ◽

Federica Sabuzi

Keyword(s):

Metal Oxides ◽

Phosphonic Acid ◽

Organic Molecules ◽

Building Blocks ◽

Reaction Conditions ◽

Phosphonic Acids ◽

Sustainable Improvement ◽

Phosphonate Esters ◽

First Time ◽

Complex Organic

Owing to the attractiveness of organic phosphonic acids and esters in the pharmacological field and in the functionalization of conductive metal-oxides, the research of effective synthetic protocols is pivotal. Among the others, ω-bromoalkylphosphonates are gaining particular attention because they are useful building blocks for the tailored functionalization of complex organic molecules. Hence, in this work, the optimization of Michaelis–Arbuzov reaction conditions for ω-bromoalkylphosphonates has been performed, to improve process sustainability while maintaining good yields. Synthesized ω-bromoalkylphosphonates have been successfully adopted for the synthesis of new KuQuinone phosphonate esters and, by hydrolysis, phosphonic acid KuQuinone derivatives have been obtained for the first time. Considering the high affinity with metal-oxides, KuQuinones bearing phosphonic acid terminal groups are promising candidates for biomedical and photo(electro)chemical applications.

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