Tom A. Modro

Reaction of O,O‐dialkyl alkylphosphonates with thionyl chloride. A remarkable effect of the O‐(2‐dialkylamino)ethyl substituent

Reaction of dialkyl alkylphosphonates with SOCl2 in the presence of DMF, reported by Maier, can serve as a convenient route to simple monoalkyl alkylphosphonochloridates. However, when a substrate contains a (2-dialkylamino)ethyl group as one of the ester functions, the course of the reaction is determined by the nature of the N-alkyl groups. With the NMe2 group present, reaction with SOCl2 occurs at nitrogen, and no exchange of groups at phosphorus takes place. The NEt2 group, on the other hand, directs the reaction to phosphorus, and the Maier reaction of the exchange of one ester group OR for Cl proceeds in high yields.

Synthesis and Reactivity of Bicyclic Phosphoric (and Thiophosphoric) Amides

This work summarizes studies on the preparation, structure, and reactivity of a new heterocyclic system containing phosphorus and nitrogen: 2,8-disubstituted-2,5,8-triaza-1 u 5 -phosphabicyclo[3.3.0]octane 1-oxide (and 1-sulfide).

STRUCTURAL, SPECTROSCOPIC AND REACTIVITY STUDIES ON PHOSPHORIC AMIDES

A series of non-cyclic, cyclic and bicyclic phosphotriamidates has been sythesized and their structure, NMR spectroscopic characteristics and their chemical reactivity are discussed.

The Phosphoryl and the Carbonyl Group as Hydrogen Bond Acceptors

For simple carbonyl compounds the Kassoc values were determined from the 1νOH for the donor. The obtained values are in the range 7–12, and agree well with the literature data. For selected phosphoryl compounds two sets of Kassoc values were determined—from the 1νOH, and the 1νP O shift. The former were in the range 300–600 and agree well with the literature data, indicating that the P O group is about two orders of magnitude stronger acceptor than the C O group. The values of Kassoc determined from the 1νP O shifts were much lower and scattered, indicating that the IR absorption band of the P O group shows weak response to the involvement in the hydrogen bonding. For the β-diphosphoryl, or for the 1,3-ketophosphoryl systems, no evidence for the enolization involving the P O function was found.

15N NMR Study of the P-N Bonding in Phosphoric Amides

Abstract A series of phosphoric amidodiesters, diamidoesters and triamides was prepared and their 31P and15 N NMR spectra were recorded in order to evaluate the major structural factors that determine the chemical shifts and coupling contants values. Considering the equation expressing the structural effects on shielding[1].