Bibrachial ligands from sterically protected tetra-azamacrocycles. Synthesis of bis(N-2-cyanoethyl)tet-a and the crystal structure of its copper(II) complex

Robert W. Hay; Thomas Clifford; Juliene Klein; Philip Lightfoot

doi:10.1016/0277-5387(95)00511-0

Bibrachial ligands from sterically protected tetra-azamacrocycles. Synthesis of bis(N-2-cyanoethyl)tet-a and the crystal structure of its copper(II) complex

Robert W. Hay^*, Thomas Clifford, Juliene Klein, Philip Lightfoot

^*Corresponding author for this work

School of Chemistry

Research output: Contribution to journal › Article › peer-review

Abstract

The preparation of the ligand bis(N-2-cyanoethyl)-C-meso-5,7,7,12,14-hexamethyl-1,4,8,11-tetra- azacyclotetradecane (L) is described. The ligand can be reduced with H₂/Raney nickel in the presence of NaBH₄ to give the bis(N-3-aminopropyl) derivative. The red copper(II) complex [CuL](ClO₄) · 0.5 MeOH has been characterised by X-ray crystallography. The complex has v(C≡N) at 2225 cm^-1 identical to that found in the free ligand, indicating that there is no interaction between the central metal ion and the pendant cyanoethyl groups. The crystal structure confirms that the copper(II) is four-coordinate and planar with the four ring nitrogens acting as donors. The Cu-N bond lengths are 2.068(6) and 1.980(5) Å. The macrocyclic ligand has the centrosymmetric trans-III configuration with chair six-membered chelate rings and gauche five-membered rings. The methyl groups on C(3) and C(5) are equatorial. Published by Elsevier Science Ltd.

Original language	English
Pages (from-to)	2315-2319
Number of pages	5
Journal	Polyhedron
Volume	15
Issue number	14
DOIs	https://doi.org/10.1016/0277-5387(95)00511-0
Publication status	Published - 1 Jan 1996

Access to Document

10.1016/0277-5387(95)00511-0

Cite this

@article{b869dd70a1a94832b75875e359fb6c7c,

title = "Bibrachial ligands from sterically protected tetra-azamacrocycles. Synthesis of bis(N-2-cyanoethyl)tet-a and the crystal structure of its copper(II) complex",

abstract = "The preparation of the ligand bis(N-2-cyanoethyl)-C-meso-5,7,7,12,14-hexamethyl-1,4,8,11-tetra- azacyclotetradecane (L) is described. The ligand can be reduced with H2/Raney nickel in the presence of NaBH4 to give the bis(N-3-aminopropyl) derivative. The red copper(II) complex [CuL](ClO4) · 0.5 MeOH has been characterised by X-ray crystallography. The complex has v(C≡N) at 2225 cm-1 identical to that found in the free ligand, indicating that there is no interaction between the central metal ion and the pendant cyanoethyl groups. The crystal structure confirms that the copper(II) is four-coordinate and planar with the four ring nitrogens acting as donors. The Cu-N bond lengths are 2.068(6) and 1.980(5) {\AA}. The macrocyclic ligand has the centrosymmetric trans-III configuration with chair six-membered chelate rings and gauche five-membered rings. The methyl groups on C(3) and C(5) are equatorial. Published by Elsevier Science Ltd.",

author = "Hay, {Robert W.} and Thomas Clifford and Juliene Klein and Philip Lightfoot",

year = "1996",

month = jan,

day = "1",

doi = "10.1016/0277-5387(95)00511-0",

language = "English",

volume = "15",

pages = "2315--2319",

journal = "Polyhedron",

issn = "0277-5387",

publisher = "Elsevier",

number = "14",

}

TY - JOUR

T1 - Bibrachial ligands from sterically protected tetra-azamacrocycles. Synthesis of bis(N-2-cyanoethyl)tet-a and the crystal structure of its copper(II) complex

AU - Hay, Robert W.

AU - Clifford, Thomas

AU - Klein, Juliene

AU - Lightfoot, Philip

PY - 1996/1/1

Y1 - 1996/1/1

N2 - The preparation of the ligand bis(N-2-cyanoethyl)-C-meso-5,7,7,12,14-hexamethyl-1,4,8,11-tetra- azacyclotetradecane (L) is described. The ligand can be reduced with H2/Raney nickel in the presence of NaBH4 to give the bis(N-3-aminopropyl) derivative. The red copper(II) complex [CuL](ClO4) · 0.5 MeOH has been characterised by X-ray crystallography. The complex has v(C≡N) at 2225 cm-1 identical to that found in the free ligand, indicating that there is no interaction between the central metal ion and the pendant cyanoethyl groups. The crystal structure confirms that the copper(II) is four-coordinate and planar with the four ring nitrogens acting as donors. The Cu-N bond lengths are 2.068(6) and 1.980(5) Å. The macrocyclic ligand has the centrosymmetric trans-III configuration with chair six-membered chelate rings and gauche five-membered rings. The methyl groups on C(3) and C(5) are equatorial. Published by Elsevier Science Ltd.

AB - The preparation of the ligand bis(N-2-cyanoethyl)-C-meso-5,7,7,12,14-hexamethyl-1,4,8,11-tetra- azacyclotetradecane (L) is described. The ligand can be reduced with H2/Raney nickel in the presence of NaBH4 to give the bis(N-3-aminopropyl) derivative. The red copper(II) complex [CuL](ClO4) · 0.5 MeOH has been characterised by X-ray crystallography. The complex has v(C≡N) at 2225 cm-1 identical to that found in the free ligand, indicating that there is no interaction between the central metal ion and the pendant cyanoethyl groups. The crystal structure confirms that the copper(II) is four-coordinate and planar with the four ring nitrogens acting as donors. The Cu-N bond lengths are 2.068(6) and 1.980(5) Å. The macrocyclic ligand has the centrosymmetric trans-III configuration with chair six-membered chelate rings and gauche five-membered rings. The methyl groups on C(3) and C(5) are equatorial. Published by Elsevier Science Ltd.

UR - http://www.scopus.com/inward/record.url?scp=0012341920&partnerID=8YFLogxK

U2 - 10.1016/0277-5387(95)00511-0

DO - 10.1016/0277-5387(95)00511-0

M3 - Article

AN - SCOPUS:0012341920

SN - 0277-5387

VL - 15

SP - 2315

EP - 2319

JO - Polyhedron

JF - Polyhedron

IS - 14

ER -

Bibrachial ligands from sterically protected tetra-azamacrocycles. Synthesis of bis(N-2-cyanoethyl)tet-a and the crystal structure of its copper(II) complex

Abstract

Access to Document

Other files and links

Fingerprint

Cite this