52601-77-1Relevant articles and documents
The rational design, synthesis and demonstration of the recognition and binding of a diaza-dioxa-12-crown-4 diphosphonate macrocycle to all crystal growth faces of barium sulfate
Bosbach, Dirk,Coveney, Peter V.,Griffin, Jonathan L.W.,Putnis, Andrew,Risthaus, Peter,Stackhouse, Stephen,Whiting, Andrew
, p. 1238 - 1245 (2007/10/03)
Computer-aided molecular design and virtual screening of a series of amino phosphonic acid derivatives were used to probe the probable interaction of these compounds as potential crystal growth inhibitors of barium sulfate, as judged by their ability to bind efficiently to all of the possible growing faces. As a result, a diphosphonic acid derivative of a 1,7-dioxa-4,10-diaza-12-crown-4 system 5 was proposed as a potential inhibitor of barium sulfate crystallisation. A subsequent synthesis of this macrocycle was developed, together with other larger-ring oxa-aza crown derivatives. Macrocycle 5 proved to be a highly efficient inhibitor of barium sulfate crystal growth at a level of 0.096 mM, as evidenced by the changes brought about in crystal morphology. Work was therefore undertaken to probe the mechanism of action of 5 using adsorption isotherms, mixed flow reactor and atomic force microscopy (AFM) measurements. It was possible to show that 5 inhibits effectively in solution by covering the growing surfaces, as observed on the 001 surface, effectively inhibiting two-dimensional nucleation as well as monolayer-step growth.
An Alternative Synthesis of Cyclic Aza Compounds
Boerjesson, L.,Welch, C. J.
, p. 621 - 626 (2007/10/02)
A series of cyclic mono-, di- and poly-aza compounds has been synthesised in moderate to good yields by reaction of p-toluenesulfonamide and either α,ω-ditosylates or α,ω-dichlorides.
MACROHETEROCYCLES. PART 44. FACILE SYNTHESIS OF AZACROWN ETHERS AND CRYPTANDS IN A TWO-PHASE SYSTEM
Lukyanenko, Nikolai G.,Basok, Stepan S.,Filonova, Lyubov K.
, p. 3141 - 3148 (2007/10/02)
A facile procedure is proposed for the preparation of azacrown ethers and cryptands by condensation of dibromides or ethylene glycol bis(toluene-p-sulphonate)s with acyclic bis(sulphonamide)s or with bisdiazacrown ethers, respectively.The reaction was carried out in a two-phase system of aqueous alkali-toluene (benzene)in the presence of quaternary ammonium salts as phase transfer catalysts.The catalytic activity decreased in the sequence: Bu4NI ca.Bu4NBr > Bu4NCl > Bu4NHSO4 > Et3NCH2C6H5NCl.Maximum yields of twelve-membered azacrown ethers are obtained when lithium hydroxide is used, while crown ethers of larger size are observed in the presence of sodium or potassium hydroxides; this may be due to a template effect.
MACROHETEROCYCES. XXXVI. A CONVENIENT METHOD FOR SYNTHESIS OF DI- AND POLYAZACROWN ETHERS
Luk'yanenko, N.G.,Basok, S.S.,Filonova, L.K.
, p. 1562 - 1571 (2007/10/02)
A method is proposed for the production of di- and polyazacrown ethers by the condensation of bissulfonamides with dibromides or ditosyloxy derivatives in a two-phase aqueous alkali-toluene (benzene) system.The optimum concentration range for the substrate and the alkylating agent is 0.017-0.1 M.The catalytic activity of the quaternary ammonium salts decreases in the order (Bu)4NI > (Bu4)NBr > (Bu4)NCl > (Bu4)NHSO4 > (C2H5)3C6H5CH2NCl >> (Et)4NI > (Et)4NBr.The highest yields of te 12-membered azacrown ethers are obtained in the presence of lithium hyroxide, and the largest yields of the crown ethers with larger ring sizes are obtained in the presence of sodium or potassium hydroxide, and this is probably due to the matrix effects of the cation.
Efficient Synthesis of N,N'-Dimethyl Diazacoronands
Ostaszewski, Ryszard,Jacobsson, Ulla,Jurczak, Janusz
, p. 221 - 228 (2007/10/02)
Modification of the Richman and Atkins method for preparation of symmetric and nonsymmetric bis-(p-toluenesulphonyl) diazacoronands is reported.The one-pot transformation of these compounds into N,N'-dimethyl diazacoronands is also described.
