Enantioselectivity of nickel(II) and copper(II) complexes of Schiff bases derived from amino acids and (S)-o-[(N-benzylprolyl)amino]-acetophenone or (S)-o-[(N-benzylprolyl)amino]benzaldehyde. Crystal and molecular structures of [Ni{(S)-bap-(S)-Val}] and [Cu{(S)-bap-(S)-Val}]
作者:Yuri N. Belokon、Victor I. Maleyev、Sergei V. Vitt、Mikhail G. Ryzhov、Yuri D. Kondrashov、Sergei N. Golubev、Yuri P. Vauchskii、Anna I. Kazika、Marina I. Novikova、Pavel A. Krasutskii、Aleksandr G. Yurchenko、Inna L. Dubchak、Valeri E. Shklover、Yuri T. Struchkov、Vladimir I. Bakhmutov、Vasili M. Belikov
DOI:10.1039/dt9850000017
日期:——
crystallographic analysis. The kinetic CH-acidity and deuterium exchange of the hydrogen of an amino acid moiety under the action of bases has been studied. The deuterium exchange is accompained with epimerization which results in 80% excess of the (S)-2-[2H]amino acid. The stereoselectivity in the nickel complexes has been found to be higher than in the copper ones. The epimerization rate constant lies
衍生自(S)-o -[(N-苄基脯氨酰基)氨基]-苯乙酮[(S)-bap]和氨基酸(aa):甘氨酸的Schiff碱的铜(II)和镍(II)配合物,(R)和(S)-和(S)-缬氨酸(val),(R)-和(S)-金刚烷-1-基丙氨酸和(R)-和(S)-金刚烷-1-基甘氨酸已经合成。配合物的结构已通过物理和化学方法确定;另外[Cu (S)-bap-(S)-Val}]和[Ni (S)-bap-((S)-Val}]已经通过X射线晶体学分析确定。研究了在碱的作用下氨基酸部分氢的动力学CH酸度和氘交换。氘交换accompained与差向异构化,其结果以80%的过量的(的小号)-2- [ 2 H]氨基酸。已发现镍络合物中的立体选择性高于铜络合物中的立体选择性。差向异构速率常数在5×10 –4 –1.2×10 –1 dm 3 mol –1 s –1的范围内。观察到的立体选择性效应是根据X来解释的射线分析,圆二色性和1