第四級アンモニウム塩の液-液分配挙動

1価陰イオンを対イオンとする第四級アンモニウム塩,テトラフェニルアルソニウム塩,テトラフェニルホスホニウム塩の抽出挙動考察のために,炭素数及び形状の異なる16種の陽イオンを用いて水-クロロホルム系での抽出定数を求めた.得られた抽出定数から次の知見を得た.(1) 1価無機陰イオンの抽出性は結晶イオン半径の大きいものほど良く,過塩素酸イオン>チオシアン酸イオン>ヨウ化物イオン>四フッ化ホウ素イオン>臭化物イオン>硝酸イオン>塩化物イオン>亜硝酸イオン>水酸イオン>フッ化物イオンの順となった. (2) アルキル鎖のメチルン基一つ当たりの抽出定数への寄与分は0.59(log単位)であり,フェニル基,ナフチル基の寄与分は2.90, 4.43であった. (3) 炭素数の同じ陽イオンの抽出性は, R-N(CH(3))(3)+>R'(4)N(+)>(C(6)H(5))(4)P(+)≈(C(6)H(5))(4)As+の順となった.これらの知見を基にイオン会合体の抽出定数の推定についても考察し,計算値と実測値との良い一致をみた.

The ion association extraction of quaternary ammonium ions with univalent anions was carried out. The extraction constants (log K(ex)) for these ion-as-sociates between aqueous and chloroform phases were determined. The linear relationship was obtained between log K(ex) and the number of carbon atoms in quaternary ammonium ion, and the contribution of a methylene group to the extraction constant, π(CH(2)), was on the average 0.59. The order of the extractability of inorganic anions was F(-)R'(4)N(+)>(C(6)H(5))(4)P(+)≈(C(6)H(5))(4)(-)As(+), and the differences in log K(ex) between the respective cations in this order averaged 1.2 and 1.1 in turn. The π values for C(6)H(5)- and C(10)H(7)(-) groups were 2.90 and 4.43, respectively. By using these empirical parameters, the extraction constants for several ion associates were estimated, and the extraction constants calculated were in good agreement with those obtained experimentally in this work and those reported by other workers.