Synthesis of pyridine-based polyaminocarboxylic ligands bearing a thioalkyl anchor

A bicyclic tetraazatriacetic chelating agent containing a thioalkyl pendant group was prepared. Four synthetic routes have been investigated via a Mitsunobu reaction from 2,4-[bishydroxymethyl]-3-hydroxy-pyridine 1. Deprotection of trityl thioether compound 5c led to ligand 6c in 22% overall yield from the starting 3-hydroxypyridine.     

Host (nanopores of zeolite-Y)/guest (Co(II)-azamacrocyclic complexes) nanocomposite materials: synthesis,characterization and catalytic epoxidation of styrene with molecular oxygen

A series of Co(II) azamacrocyclic complexes, 12 Brunel, D, Bellocq, N, Sutra, P, Cauvel, A, Lasperas, M, Moreau, P, Di Renzo, F, Galarneau, A and Fajula, F. 1998. Coord. Chem. Rev., 178–180: 1085[Crossref], [Web of Science ®] , [Google Scholar]aneN₄, 14 De Vos, DE, Dams, M, Sels, BF and Jacobs, PA. 2002. Chem. Rev., 102: 3615[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]aneN₄, Bzo₂ 12 Brunel, D, Bellocq, N, Sutra, P, Cauvel, A, Lasperas, M, Moreau, P, Di Renzo, F, Galarneau, A and Fajula, F. 1998. Coord. Chem. Rev., 178–180: 1085[Crossref], [Web of Science ®] , [Google Scholar]aneN₄ and Bzo₂ 14 De Vos, DE, Dams, M, Sels, BF and Jacobs, PA. 2002. Chem. Rev., 102: 3615[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]aneN₄, have been encapsulated in the nanocavity of zeolite-Y by a one pot template condensation reaction. Co(II) complexes with azamacrocyclic ligands were entrapped in the nanocavity of zeolite-Y by a two-step process in the liquid phase: (i) adsorption of [bis(diamine)cobalt(II)], [Co(N–N)₂]-NaY, in the supercages of the zeolite, and (ii) in situ condensation of the cobalt(II) precursor complex with diethyloxalate. The new host/guest nanocomposite materials (HGNM) have been characterized by FTIR, DRS and UV-Vis spectroscopic techniques, XRD and elemental analysis, as well as nitrogen adsorption. These complexes (neat and HGNM) were used for epoxidation of styrene with O₂ as oxidant in different solvents. Electronic spectra of the reaction mixture indicated oxidation proceeds through a free radical mechanism.     

Synthesis of azamacrocycles via a Mitsunobu reaction

Reaction of pernosylated diethylenetriamine and 2-substituted propane-1,3-diols in dry THF in the presence of triphenylphosphine and diisopropyl azodicarboxylate gives the corresponding protected 9-substituted 1,4,7-triazacyclodecanes. The Mitsunobu reaction was also used in the preparation of 3-substituted 1,5,9-triazacyclododecanes and macrocyclic pyridine derivatives.     

The synthesis and structure of trans-di(cyano-κ)-(trans-6,13-dimethyl-6,13-bis(propionylamido)-1,4,8,11-tetraazacyclotetradecane-κ)cobalt(III) perchlorate dihydrate

trans-Di(cyano-κ¹)-(trans-6,13-dimethyl-6,13-bis(propionylamido)-1,4,8,11-tetraazacyclotetradecane-κ⁴)cobalt(III) perchlorate dihydrate, trans-[Co(C₁₈H₃₈N₆O₂)(CN)₂)]ClO₄ · 2H₂O, is formed by reaction of trans-[Co(diam)(CN)₂]ClO₄ · 2H₂O (diam = trans-6,13-diamino-6,13-dimethyl-1,4,8,11-tetraazacyclotetradecane) with propionic anhydride in DMF. The centrosymmetrical cation has the azamacrocycle in planar coordination by the four secondary amine nitrogen atoms of the azamacrocycle, with Co–N = 1.979(2) and 1.968(2) Å and with trans cyano groups with Co–C = 1.920(2) Å. The propionylamido substituents are axially oriented, with the terminal methyl group disordered over two sites.     

The structures of some (hexamethyl-1,5,9,13-tetraazacyclohexadecadiene)copper(II) compounds

The structure of the crystalline azamacrocyclic product formed by reaction of bis(propane-1,3-diamine)copper(II) perchlorate with acetone has been determined as N-rac-(6,8,8,14,16,16-hexamethyl-1,5,9,13-tetraazacyclohexadeca-5,13-diene)copper(II) · N-meso-(6,8,8,14,14,16-hexamethyl-1,5,9,13-tetraazacyclohexadeca-5,16(1)-diene)copper(II) perchlorate, with the cis, 5,16(1)-diene, and trans, 5,13-diene, isomeric cations co-crystallised. The structures of three compounds crystallised from solutions of this mixture have been determined. N-rac-(6,8,8,14,14,16-hexamethyl-1,5,9,13-tetraazacyclohexadeca-5,16(1)-diene)copper(II) tetrachlorozincate has an irregular flattened tetrahedral coordination geometry with trans-N-Cu-N angles of 139.27(8)° and 155.94(8)°. (Hexamethyl-1,5,9,13-tetraazacyclohexadecadiene)(thiocyanato-N)copper(II) perchlorate has twofold symmetrical square-pyramidal cations. A (μ-cyano)-tetracyanonickelate(II) compound has two (hexamethyl-1,5,9,13-tetraazacyclohexadecadiene)copper(II) cations each with a single axially coordinated tetracyanonickelate(II) group. The compounds, except for the tetrachlorozincate(II) salt, show disorder in the location of the imine functions and axial methyl substituents, attributed to co-crystallisation of enantiomers for the N-rac-trans isomer and/or of rotated arrangements of the N-meso-cis isomer. For the thiocyanato and tetracyanonickelato compounds this disorder precluded unambiguous assignment of configuration.     

Synthesis and structures of (13-hydroxylamino-5,7,7,13-tetramethyl-1,4,8,11-tetraazacyclotetradec-4-ene-κ)nickel(II) tetrachlorozincate(II) and (13-azonium-5,5,7,13-tetramethyl-1,4,8,11-tetraazacyclotetradecane-κ)nickel(II) tetrachlorozincate(II) chloride 2.25 water

Zinc/acid reduction of the nitro function of (5,7,7,13-tetramethyl-13-nitro-1,4,8,11-tetraazacyclotetradec-4-ene)nickel(II) yields (13-hydroxylamino-5,7,7,13-tetramethyl-1,4,8,11-tetraazacyclotetradec-4-ene)nickel(II), isolated as the tetrachlorozincate salt, for which the structure is reported. This has singlet ground state nickel(II) in square-planar coordination by the three amine and the imine nitrogen atoms of the macrocycle. There is no interaction between the nickel(II) ion and the axially oriented hydroxylamino group.Zinc/acid reduction of the nitro function of (5,5,7,13-tetramethyl-13-nitro-1,4,8,11-tetraazacyclotetradecane)nickel(II) yields (13-amino-5,5,7,13-tetramethyl-1,4,8,11-tetraazacyclotetradecane)nickel(II), isolated from acid solution as (13-azonium-5,5,7,13-tetramethyl-1,4,8,11-tetraazacyclotetradecane-κ⁴)nickel(II) tetrachlorozincate(II) chloride 2.25 water, for which the structure is reported. The two independent cations have singlet ground state nickel(II) in square-planar coordination by the four secondary amine nitrogen atoms of the macrocycle, with the protonated amine substituent axially oriented.The cations of both compounds show disorder in the location of the axial methyl component of the gem-dimethyl group, manifest as reversal of the trimethyl substituted 1,3-amine-imine or 1,3-diamine chelate rings, arising from co-crystallisation of enantiomers.     

Bi－氮杂大环配合物极谱波的研究──纯锡中铋的测定

本文研究了作者合成的氮杂大环化合物与铋形成的配合物的极谱性能，建立了一个测定铋的新体系。方法用于测定纯锡样品中的微量铋，结果满意。     

The structure of N-meso-(6,8,8,14,16,16-hexamethyl-1,5,9,13-tetraazacyclohexadeca-5,13-diene)nickel(II) chloro(isothiocyanato)zincate(II)

A yellow compound which was crystallised from a solution of (6,8,8,14,16,16-hexamethyl-1,5,9,13-tetraazacyclohexadeca-5,13-diene)bis(isothiocyanato)nickel(II) in aqueous zinc(II) chloride has cations with singlet ground state nickel(II) in square-planar coordination by the nitrogen atoms of the macrocycle. The asymmetric unit has two similar cations. The N₄ group of one cation is near coplanar (r.m.s. displacements ±0.009(1) Å, with Ni displaced by 0.048(1) Å from this plane) while the other cation has significant tetrahedral twisting of the N₄ group (r.m.s. displacements of N atoms ±0.126(2) Å, with Ni displaced by 0.027(2) Å from this plane). The mean Ni–N distances are Ni–N_amine = 1.950(6) and Ni–N_imine = 1.897(6) Å. Both cations have N-meso configurations with saddle conformations, with the substituted chelate rings in boat conformations tilted to one side of the NiN₄ ‘plane’ and the unsubstituted chelate rings tilted to the other side, one in a boat conformation and the other with the central methylene group disordered, the components forming boat {s.o.f. 0.70(1) and 0.74(1) for the two cations} and chair conformation chelate rings. The counter-ions have tetrahedrally coordinated zinc(II) ions, one as [ZnCl₂(NCS)₂]²⁻ ions and the other with one ligand site with disordered Cl⁻ {s.o.f. 0.78(1)} and NCS⁻ ligands, i.e. with disordered [ZnCl₂(NCS)₂]²⁻ and [ZnCl(NCS)₃]²⁻ ions, with an overall composition of [Ni(trans-Me₆[16]diene)][ZnCl_1.9(NCS)_2.1].     

Synthesis and crystal structure of a macrocyclic complex precursor: Bis-(2-amino-1-methyliminobenzene)1,2-ethane nickel(II) dichloride

NiLCIl₂ (L?=?bis-(2-amino-1-methyliminobenzene)1,2-ethane) crystallizes in space group P-1 with a?=?9.042(2), b?=?10.263(10), c?=?11.045(2) Å, α?=?94.76(10), β?=?108.30(10), γ?= 109.86(10)°, Z?=?2, and represents a precursor of a tetradentate azamacrocyclic complex. The structure is stabilized by a system of intramolecular and intermolecular H-bonding involving chloride ions and nitrogen atoms. The coordination geometry about nickel(II) is slightly distorted octahedral.