Abstract
It is known that introduction of the side chain containing the atom which has coordination capability on crown ether increases the stability constant of its metal complex. We examine the effect of a kind of a coordinative atom of this side arm and electric density on coordinateve atom etc. about 2-position halide substituent of N-(2-substituted phenyl)-monoaza-crown-ether. And, the temperature dependency of stability constant was also examined by carrying out the UV titration at 15oC, 25oC, and 35oC for the purpose of the elucidation of the ortho substituent role and the factor which decide the stability constant. Metal ion for present measurement is Na+, Li+ and Mg2+.The stability constant of Na+ and Li+ complex of N-(2-halogenated phenyl)-15-crown-5-ether were larger than that of N-phenyl-15-crown-5-ether. In Mg2+ complex, since the stability constant of the 2-F and 2-Cl substituted crown were larger than that of 4-Cl substituted crown, the stabilization effect of 2-F and 2-Cl was observed. It seems to electrostatically stabilize by the 2-halogen atom, because the increase is observed at the order of F>Cl>Br>I. On the temperature dependency of stability constant, the stability constant increases at the high temperature in Mg2+ complex, while that increases at the low temperature in Na+ and Li+ complex.
