Copper(I) Coordination Chemistry of (Pyridylmethyl)amide Ligands

Abstract

Copper(I) chloro complexes were synthesized with a family of ligands, HL(R) [HL(R) = N-(2-pyridylmethyl)acetamide, R = null; 2-phenyl-N-(2-pyridylmethyl)acetamide, R = Ph; 2,2-dimethyl-N-(2-pyridylmethyl)propionamide, R = Me3; 2,2,2-triphenyl-N-(2-pyridylmethyl)acetamide, R = Ph3)]. Five complexes were synthesized from the respective ligand and cuprous chloride: [Cu(HL)Cl]n (1), [Cu2(HL)4Cl2] (2), [Cu2(HL(Ph))2(CH3CN)2Cl2] (3), [Cu2(HL(Ph)3)2Cl2] (4), and [Cu(HL(Me)3)2Cl] (5). X-ray crystal structures reveal that for all complexes the ligands coordinate to the Cu in a monodentate fashion, and inter- or intramolecular hydrogen-bonding interactions formed between the amide NH group and either amide C=O or chloro groups stabilize these complexes in the solid state and strongly influence the structures formed. Complexes 1-5 display a range of structural motifs, depending on the size of the ligand substituent groups, hydrogen bonding, and the stoichiometry of the starting materials, including a one-dimensional coordination polymer chain (1) and binuclear (2-4) or mononuclear (5) structures.

Synthesis and structures of three heterobimetallic compounds based on a new ferrocenyl pyridine ligand

“…The pyridylmethylamide group may also contribute to the construction of supramolecular assemblies by forming hydrogen bonds using its amino groups and -stacking interactions of pyridyl rings. A series of high-nuclear copper complexes bearing the pyridylmethylamide group have been reported by Houser and his coworkers [12][13][14][15]. The coordination geometry of the central metal is substantially influenced by the steric effect of the substituents of the amide, the use of base and even the starting materials [16].…”

Syntheses and structures of a phenoxo-bridged copper(II) distorted cubane and related complexes with 2-hydroxy-N-(2-pyridylalkyl)benzamide ligands

“…Two new ligands were designed based on pyridylamide ligands previously synthesized in our laboratory [5][6][7][8][9][10][11][12], by replacing the alkyl or aryl functional group in HL R with a phenol group (see Scheme 1). 2-Hydroxyphenyl-N-(2-pyridylmethyl)acetamide (HL PhOH ) and 2-hydroxyphenyl-N-(2-pyridylethyl)acetamide (HL PhOH 0 ) differ only in the number of carbon atoms connecting the pyridyl group to the amide group.…”

“…There is only one reported hydroxo-bridged, four-coordinate copper complex with an open cubane-like Cu 4 O 4 framework [3]. Here, we reported the first four-coordinate phenoxo-bridged tetranuclear copper complex with distorted cubane geometry.Recently, our laboratory has focused on the synthesis and characterization of copper clusters using a series of pyridylmethylamide ligands [4][5][6][7][8][9][10]. Pyridyl amide ligands exhibit totally different coordination modes depending on the presence or absence of base used in the synthesis of complexes, since a base will deprotonate the amide group.…”

“…More recently, other multicopper complexes with pyridylmethylamide ligands containing alkyl or aryl groups in place of the methyl group in HL (HL Ph , HL Me3 , and HL Ph3 ) were also reported, including hydroxo-and methoxo-bridged complexes [Cu 4 (L Ph ) 4 (OH) 2 ] (ClO 4 ) 2 , [Cu 2 (HL Me3 ) 2 (OMe) 2 ](OTf) 2 and [Cu 2 (HL Ph3 ) 2 (OMe) 2 ](OTf) 2 [8]. Here we report two new ligands and their copper(II) complexes where we have introduced a phenol group into the pyridyl amide ligand as shown in Scheme 1.Two new ligands were designed based on pyridylamide ligands previously synthesized in our laboratory [5][6][7][8][9][10][11][12], by replacing the alkyl or aryl functional group in HL R with a phenol group (see Scheme 1). 2-Hydroxyphenyl-N-(2-pyridylmethyl)acetamide (HL PhOH ) and 2-hydroxyphenyl-N-(2-pyridylethyl)acetamide (HL PhOH 0 ) differ only in the number of carbon atoms connecting the pyridyl group to the amide group.…”

Cuprous Chloride Catalyzed Isomerization of 3-Chloro-1-butene to Crotyl Chloride

“…Young 等 [7] 发 现, 3-溴-1-丁烯和 1-溴-2-丁烯在 100 ℃平衡时前者占 15%, 后者 85%; Kharasch 等 [8,9] 发现路易斯酸对 CB 异构 化有催化作用; CB 在氯化亚铜为催化剂、甲苯为溶剂、 温度为 60 ℃的反应体系中达到反应平衡时, CB 含量为 26%, CC 含量为 74%. [10,11] . 另外, CuCl [18] , 因此在不加催化剂和低 温的条件下 CB 发生异构化反应速度很慢.…”