60147-30-0Relevant articles and documents
Synthesis and Separating Properties of Tris(Merrifield Peptide Resin)
Kim, Dong Won,Kim, Chang Suk,Lee, Nam-Soo,Ryu, Haiil,Kim, Jong Seung,Jang, Young Hun
, p. 107 - 112 (2007/10/03)
A triazacrown ion exchanger, 1,13,16-trioxa-4,7,10-triazacyclooctadecane (TOTA)-4,7,10-tris(Merrifield peptide resin) was synthesized. This resin has a capacity of 0.1 meq/g dry resin. The resin was used for the elution chromatographic separation of lithi
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.