27353-29-3Relevant articles and documents
Synthesis and acid-base properties of α-aminophosphoryl compounds
Zakharov,Nuriazdanova,Garifzyanov,Galkin,Cherkasov
, p. 873 - 881 (2004)
α-Aminophosphoryl compounds of the phosphonate, phosphine oxide, and α,ω-bis(phosphine oxide) series and some of their thiophosphoryl analogs were synthesized. Potentiometric measurements of the pKa of the conjugate acids revealed an insignificant effect of variation of substituents on the phosphorus, nitrogen, and α-carbon atoms on the basicity of the phosphorylated amines. The latter are weak bases. Organophosphorus groups decrease the basicity of the amines by almost 5 pK a units. The role of the hydrophobic effect and intramolecular H-bonding in the obtained substances was discussed.
Copper-catalyzed α-amination of phosphonates and phosphine oxides: A direct approach to α-amino phosphonic acids and derivatives
McDonald, Stacey L.,Wang, Qiu
supporting information, p. 1867 - 1871 (2014/03/21)
A direct approach to important α-amino phosphonic acids and its derivatives has been developed by using copper-catalyzed electrophilic amination of α-phosphonate zincates with O-acyl hydroxylamines. This amination provides the first example of C=N bond formation which directly introduces acyclic and cyclic amines to the α-position of phosphonates in one step. The reaction is readily promoted at room temperature with as little as 0.5 mol % of catalyst, and demonstrates high efficiency on a broad substrate scope. A direct approach to important α-amino phosphonic acids and derivatives, by using copper-catalyzed electrophilic amination of α-phosphonate zincates using O-acylhydroxylamines, is described. This amination is the first example of C=N bond formation which directly introduces acyclic and cyclic amines to the α-position of phosphonates in one step. The reaction proceeds at room temperature with as little as 0.5 mol % of the catalyst. Copyright
Design and synthesis of macrocyclic ligands for specific interaction with crystalline ettringite and demonstration of a viable mechanism for the setting of cement
Griffin, Jonathan L. W.,Coveney, Peter V.,Whiting, Andrew,Davey, Roger
, p. 1973 - 1981 (2007/10/03)
Cementitious materials are among those most widely used by mankind while being among the least well understood. The detailed physicochemical processes involved in the hydration and setting of cement slurries are very complex, and a clearly defined quantitative account is still lacking: indeed, even the composition of the cement powder itself is not known exactly. Still less has there been any understanding of the mechanism by which numerous known retarders of the cement setting process act. In this article, we detail the synthesis of novel macrocyclic organophosphonate retarders 1a and 2a which were developed by rational methods. Attempts to synthesise these compounds as phosphonate ester derivatives were universally unsuccessful, however direct modification of the parent hexaaza-(3) and trioxatriaza-18-crown-6 (5) derivatives was successful, to provide the phosphonic acids 1b and 2b respectively. Subsequent testing of these compounds showed their ability to inhibit the growth of crystalline ettringite and delay the setting of cement. These results support the hypothesis that the formation of crystalline ettringite is the rate determining step in the setting of cement.
