Copper(II) complexes of novel N-alkylated derivatives of cis,cis-1,3,5-triaminocyclohexane. 1. Preparation and structure.
Copper(II) complexes of novel N-alkylated derivatives of cis,cis-1,3,5-triaminocyclohexane. 1. Preparation and structure.
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顺式,顺式-1,3,5-三氨基环己烷的新型N-烷基化衍生物的铜(II)络合物。
DOI：
10.1021/ic000829e
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发表时间：
2001
影响因子：
4.6
通讯作者：
Planalp,RP
中科院分区：
文献类型：
--
作者：
Park,G;Shao,J;Lu,FH;Rogers,RD;Chasteen,ND;Brechbiel,MW;Planalp,RP
通过N-保护的顺-1，3，5-三氨基环己烷(TACH)的烷基化和酸脱保护反应，合成了顺式-1，3，5-三氨基环己烷(TACH)的N，N‘，N’- ‘-三烷基化衍生物(TACH-R3)，得到N-甲基、N-乙基和N-正丙基衍生物作为它们的三氢溴化盐。分别由TACH和丙二醛或呋喃-2-甲醛生成亚胺，然后还原亚胺，合成了TACH-新戊基3和TACH-呋喃3衍生物。用CuCl2在甲醇或甲醇−-Et2O溶剂中合成了配合物[Cu(tach-R3)Cl2](R=Me、Et、n-Pr、CH2-2-噻吩基和CH2-2-呋喃)。[Cu(tach-Et3)Br0.8Cl1.2](Pnma，a=8.2265(1)ä，b=12.5313(1)ä，c=15.3587(3)ä，Z=4)的结晶学表征表明，CuN3X2配位球体为四方锥体，其中一个氮施主占据顶端位置的距离(Cu−N=2.218(5)ä)略长于基氮配位(Cu−N=2.053(2)ä)。用电子顺磁共振和可见光−近红外光谱研究了[Cu(Tach-R3)Cl2]的溶液相(pH7.4缓冲液和甲醇)和固相结构。根据溶液和固态数据的对应关系，在溶液中保留了正方形金字塔结构。在水溶液中，[Cu(tach-et3)]2+(AQ)的高能UV-−-Vis光谱位移和成键参数表明，卤化物被水取代。在pH为7.4~10.1范围内，提出的水相物种为[Cu(tach-Et3)(H2O)2]2+。在pH 7.4时，配合物[Cu(TACH-ME3)]2+(AQ)不出现二聚化或形成金属−羟基物种，与其他−三胺配合物不同，如[Cu(1，4，7-三氮杂环烷)]2+(AQ)和[Cu(TACH-H3)]2+(AQ)(未烷化的TACH的络合物)。这种差异归因于TACH-R3系列中当时烷基的空间效应。
NovelN,N‘,N‘ ‘-trialkylated derivatives ofcis,cis-1,3,5-triaminocyclohexane (tach), designated tach-R3, were prepared through alkylation of N-protected tach with subsequent acid deprotection, to affordN-methyl,N-ethyl, andN-n-propyl derivatives as their trihydrobromide salts. The tach-neopentyl3and tach-furan3derivatives were prepared by formation of the imine from tach and pivaldehyde or furan-2-carboxaldehyde, respectively, followed by reduction of the imine. Complexes [Cu(tach-R3)Cl2] (R = Me, Et,n-Pr, CH2-2-thienyl, and CH2-2-furanyl) were prepared from CuCl2in MeOH or MeOH−Et2O solvent. Crystallographic characterization of [Cu(tach-Et3)Br0.8Cl1.2] (Pnma,a= 8.2265(1) Å,b= 12.5313(1) Å,c= 15.3587(3) Å,Z= 4) reveals a square-based pyramidal CuN3X2coordination sphere in which one nitrogen donor occupies the apical position at a slightly longer distance (Cu−N = 2.218(5) Å) than those of the basal nitrogens (Cu−N = 2.053(2) Å). The solution-phase (pH 7.4 buffered and methanol) and solid-phase structures of [Cu(tach-R3)Cl2] have been studied extensively by EPR and visible−near-IR spectroscopies. The square-based pyramidal structure is retained in solution, according to correspondence of solution and solid-state data. In aqueous solution, halide is replaced by water, as indicated by the high-energy UV−vis spectral shifts and bonding parameters of [Cu(tach-Et3)]2+(aq) derived from EPR data. The proposed aqueous-phase species, in the pH range 7.4 to 10.1, is [Cu(tach-Et3)(H2O)2]2+. The complex [Cu(tach-Me3)]2+(aq) does not appear to dimerize or form metal−hydroxo species at pH 7.4, in contrast to other Cu(II)−triamine complexes, e.g., [Cu(1,4,7-triazacyclononane)]2+(aq) and [Cu(tach-H3)]2+(aq) (the complex of unalkylated tach). This difference is attributed to the steric effect of theN-alkyl groups in the tach-R3series.