Syed Sirajul Hasan

Macrocyclic complexes of transition metals with divalent polyaza units

A new series of 14–16-membered hexaazamacrocyclic complexes [ML1X2] and [ML2X2] (M = CoII, NiII, CuII and ZnII; X = Cl or NO3) have been synthesized by template condensation of phenylenediamine, primary diamines and formaldehyde solution 35% in MeOH and have been characterized by i.r., 1H-n.m.r., e.p.r., and u.v. spectroscopy as well as by magnetic susceptibility and conductivity measurements. An octahedral geometry has been suggested for all the complexes.

Metal ion directed synthesis of 14–16 membered tetraimine macrocyclic complexes

A new series of 14–16 membered tetraazatetraimine macrocyclic complexes [ML1X2]-[ML3X2] [M=CoII, NiII and ZnII] and [CuL1]X2-[CuL3]X2 [X=Cl or NO3] have been synthesized by the template condensation of dibenzoylmethane with primary diamines in MeOH. The complexes were characterized by elemental analysis, i.r, 1H-n.m.r., e.p.r. and u.v-vis spectroscopy, as well as by conductivity and magnetic susceptibility measurements. The copper complexes exhibit square planar geometry, whereas an octahedral geometry is suggested for all other complexes.

Template synthesis and spectroscopic studies of highly conjugated tetraiminetetraamide macrocyclic complexes from 1,2-diphenylethane-1,2-dione dihydrazone

A new class of tetraiminetetraamide macrocyclic (Ph4[20]tetraene, N8O4, and Ph6[20]tetraene, N8O4) complexes have been prepared through the metal ion controlled reaction of 1,2-diphenylethane-1,2-dione dihydrazone (DPEDDH) with succinic acid [ML1X2] or phthalic acid [ML2X2] [M=Mn, Co, Ni, Cu or Zn; X=Cl or NO3]. The structures of the complexes have been elucidated on the basis of i.r, 1H-n.m.r, e.p.r. and electronic spectral data and conductance, as well as magnetic, properties. An octahedral geometry is assigned for all the complexes, involving coordination of the all-imine nitrogens.

Metal Complexes of 22-Niembered Mononuclear Tetraimine-Tetraamide Macrocycles: Synthesis and Characterization

Abstract Template condensation reaction of succinic acid or phthalic acid with hydrazine hydrate and 2,4-pentanedione resulted in the formuation of a new series of 22-membered tetraiminetetraamide macrocyclic complexes: dichloro/dinitrato (8, 11, 19, 22-tetraone-3, 5, 14, 16-tetramethyl-1, 2, 6, 7, 12, 13, 17, 18-octaazacyclodocosane-2, 5, 13, 16-tetraene)metal(II), [ML1X2] [M = Mn(II), Co(II), Ni(II) and Zn(II); X = CI or NO3]; (8, 11, 19, 22-tetraone-3, 5, 14, 16-tetramethyl-1, 2, 6, 7, 12, 13, 17, 18-octaazacyclodocosane-2, 5, 13, 16-tetraene)copper(II) dichloride/dinitrate [CuL1]X2; dichloro/dinitrato(9, 10, 20, 21-d ibenzo-8, 11, 19, 22-tetraone-3, 5, 14, 16-tetramethyl-1, 2, 6, 7, 12, 13, 17, 18-octaazacyclodocosane-2, 5, 13, 16-tetraene)metal(II), [ML2X2] [M = Mn(II), Co(II), Ni(II) and Zn(II); X = CI or NO3) and (9, 10, 20, 21-dibenzo-8, 11, 19, 22-tetraone-3, 5, 14, 16-tetramethyl, 2, 6, 7, 12, 13, 17, 18-octaazacyclodocosane-2, 5, 13, 16-tetraene)copper(II) dichloride/dinitrate, [CuL2]X2. These complexes have been characterized by IR, 1H NMR, EPR and electronic spectral studies, conductivity and magnetic susceptibility measurements. An octahedral geometry has been suggested for the manganese, cobalt, nickel and zinc complexes, while a square-planar geometry is proposed for the copper complexes. All complexes are stable to air.

INCORPORATION OF PEPTIDE BONDS IN THE SYNTHESIS OF POLYAZAMACROCYCLIC COMPLEXES

SummaryA new series of 15- and 16-membered dioxotetraamine macrocyclic complexes, [ML1X2] and [ML2X2] (M = MnII, CoII, NiII, CuII or ZnII; X = Cl or NO3), respectively, were prepared by reacting o-aminobenzoic acid, diaminoethane or 1,3-diaminopropane with 2,4-pentanedione in the presence of metal ions. The complexes were identified by analytical data, i.r., 1H-n.m.r., e.p.r. and u.v.-vis. spectroscopies, and by conductivity and magnetic moment measurements. They exhibit an octahedral geometry leaving the peptide oxygen uncoordinated. They are air stable and insoluble in water and most organic solvents, but soluble in DMSO and DMF. The low conductivity suggests that the complexes are non-ionic.

SPECTROSCOPIC STUDIES OF HETEROBIMETALLIC ADDUCTS OF TIN WITH Mn(ll), Co(ll), Cu(ll) AND Zn(ll)

The reaction of diketones (benzil or 2,4-pentanedione) with primary diamines (diaminoethane or 1,3-diaminopropane) in 1:2 molar ratio in the presence of MCI2 (M=Mn, Co, Ni, Cu and Zn) and SnCI4 resulted in the formation of heterobimetallic complexes of the type [CI2MLSnCI2] [L=L rL4, the respective tetradentate ligand], These compounds have been characterized on the basis of elemental analyses, IR, H NMR, UV/VIS, EPR and electronic spectral results and by conductivity and magnetic moment measurements. All the compounds are found to be non ionic. An octahedral geometry is assigned for the transition metal ions while a probable tetrahedral geometry is assigned for tin atom.