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Salah S. Massoud
Associate Professor
Ph. D., Boston University
Inorganic and Bioinorganic Chemistry
Phone: 337-482-5672 (office) & 337-482-1469 (lab.)
Fax: 337-482-5676
E-mail: ssmassoud@louisiana.edu
RESEARCH
Our research focuses on investigating and development novel metal complexes with specific structural
demands for potentially modeling biological molecules and for certain applications in material
sciences.
Bioinorganic Chemistry
This includes Catalytic hydrolysis of biological polyphosphates (ATP, GTP, ADP) and phosphate
esters. Kinetics and mechanistic studies for the role of “Metal ions” in promoting the hydrolysis of
polyphosphates (ATP, GTP, ADP) and phosphate esters using novel aqua-tetraamine-cobalt(III)
complexes. Also, the study is extended to include substitution and complex formation reactions, as
well as the metal ion-coordinating properties of pyrimidine- and purine-nucleotides. We were able to
synthesize a number of tripod tetraamine ligands such as tris[(2-pyridyl)methyl]amine (TPA), tris(2benzimidozolylmethyl)amine (TBzIm) and other related amines containing pyridyl and/or amino-ethyl
and amino-propyl arms attached to the tertiary nitrogen. The aqua-cobalt(III) complexes of these
amines will be used to promote the hydrolysis adenosine 5`-triphosphate (ATP) and phosphate esters
in an attempt to reach the enzyme level.
The second area of interest is focused on the design and synthesis of novel metal complexes of
sulfur-nitrogen-oxygen containing triazole ligands. These compounds are made to model the active
sites in some biological molecules and metalloenzymes with special emphasis on iron(III) and
cobalt(III) in nitrile hydratases (bacterial metalloenzymes that catalyze the hydration of nitriles to the
corresponding amides). In this project we intend to synthesize novel ligands with potentially sulfurnitrogen donor atoms via a heterocyclic thione compounds. The design of these compounds is based
on 4-amino-3-alkyl-1,2,4-triazole-5-thione which is used as a precursor for incorporating carboxamide
groups into the triazole skeleton. Iron(III) and cobalt(III) complexes of this class of ligands would be
synthesized and then oxidized with molecular oxygen to the corresponding sulfinato (-SO2)and/or
sulfeato (-SO) species. The effectiveness of these modified sulfur forms are the targets for studying
the hydrolysis of CH3CN and C6H5CN. Understanding the behavior of these models will allow us to
evaluate and correlate their electronic structural environment to the enzyme activity.
Inorganic Chemistry
We are also very interesting in the design and characterization of polynuclear inorganic
molecules with novel magnetic properties. These molecules may utilize useful applications in material
sciences and in the field of condensed matter physics. The strategy for synthesizing these compounds
depends on the assembly of paramagnetic centers (Cu2+ and Ni2+) via bridging ligands such as
pseudohalides (N3- and SCN-) or terephthalate anion. We are hoping to correlate the structural
parameters of the bridging compounds (geometrical factor, the M2+-X-M2+ torsion angle, and the axial
Cu-ligand bond-length) to their magnetic properties. Aside from this project, our interest is also
extended to study the factors that might affect the crystallization pathway selected by racemic solutions
of metal complexes, phenomenon nowadays is known as “conglomerate crystallization”. In this
project, a novel series of nitrito- and chloro-amine-cobalt(III) are synthesized and structurally
characterized
Different techniques are used to characterize the synthesized complexes including 1H and 13C
NMR, FAB/MAS, UV-VIS.-NIR and IR spectrophotometry. Magnetic susceptibility measurements
and molecular structure determination by X-ray diffraction are carried out in collaboration with Prof.
Ivan Bernal (University of Houston), Prof. Franz Mautner (Graz University of Technology,
Graz/Austria) and Professors A. Escuer and R. Vicente (University of Barcelona, Barcelona/Spain).
My laboratory is well equipped with the facilities required to synthesize the designed
complexes and studying their kinetic behavior: Agillent 8453 HP diode arry UV-VIS.
spectrophotometer with a thermostated bath and could be connected to SFA-20 unit for rapid kinetic
measurements, Visco Alpha Titroline Easy for automatic titration, pH meter, Mark II JM balance for
measuring magnetic susceptibility at room temperature, rotary evaporator, vacuum pump, water
purification system, computers with software installed to analyze the kinetic data.
Selected Publications
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Massoud, S. S.; Mautner, F. A., submitted, 2005. “Synthesis and Structure Determination of Two
New Dinuclear End-to-end Doubly Bridged Azido- and Thiocyanato-copper(II) Complexes
Derived from diethyldiethylenetriamine”.

Massoud, S. S.; Corfù, N. A.; Griesser, R.; Sigel, H. Chem. Eur. J. 2004, 10, 5129-5137. “AcidBase Properties of Xanthosine 5`-Monophosphate (XMP) and of Some Related Nucleobase
Derivatives in Aqueous Solution. Micro-Acidity-Constant Evaluations of the (N1)H versus
(N3)H Deprotonation Ambiguity”.

Escuer, A.; Font-Bardia, M.; Massoud, S. S.; Mautner, F. A.; Penalba, E.; Solans, X.; Vicente R.
New J. Chem. 2004, 28, 681-666. “Three New Dinuclear Copper(II) Complexes with [Cu(1,3N3)2Cu]2+ and [Cu(1,1-N3)2Cu]2+ Assymetrical Cores: Syntheses, Structure and Magnetic
Behavior”.

Massoud, S. S.; Mautner, F. A. Inorg. Chem. Commun, 2004, 7, 559-562. “Synthesis,
Characterization and Crystal Structure of 1,4-Bis(3-aminopropyl)piperazineperchloratocopper(II)
Perchlorate”.

Mukhopadhyay, U.; Bernal, I.; Massoud, S. S.; Mautner, F. A. Inorg. Chim. Acta 2004, 357,
3673-3682. “Syntheses, Structures and Some Electrochemistry of Cu(II) Complexes With
Tris[(2-pyridyl)- methyl]amine: [Cu{N(CH2-py)3}(N3)]ClO4 (I), [Cu{N(CH2-py)3}(NO2)]ClO4
(II) and [Cu{N(CH2-py)3}(NCS)]ClO4 (III)”.

Mukhopadhyay, M.; Bernal, I.; Yufit, D. S.; Howard, J. A. K.; Massa, L.; Gindulyte, A.; Todaro,
L.; Massoud, S. S. Inorg. Chim. Acta 2004, 357, 4121-4128.
“Polymorphism in
[(polyamine)Co(NO2)x]Y Crystals Caused by Changes in Torsional Angles of the (Amine)N-CoN-O Fragments. (x = 2, Y = NO3-; x = 3, Y = 0)”.

Massoud, S. S. Inorg. Chim. Acta 2002, 339C, 83-88. “Kinetics and Mechanism of the Ligand
Hydrolysis Reactions of (Hexafluoroacetylacetonato)(tetraamine)cobalt(III) Complexes.
Reactivity Patterns”.

Massoud, S. S.; Chun, H.; Bernal, I. J. Coord. Chem. 2002, 55, 619-626. “Chromium(III)
Complexes with Quadridentate Amines. Crystal Structure of [cis--Cr(triene)(C2O4)]Cl.2H2O (I)
and [Cr2(-OH)2(-tren)2]Br4.2H2O (II)”

Massoud, S. S.; Chun, H.; Wen R.; Bernal, I. J. Coord. Chem. 2002, 55, 1065-1078. “Synthesis
and Characterization of Nitrato-triamine-metal(II) Complexes. Crystal Structure of Ni(dien)(O2NO)(ONO2) (I), {Cu(dien)(-ONO2)]NO3} (II), Zn(dien)(O2NO)(ONO2) (III), Ni(Medpt)(O2NO)(ONO2) (IV) and Cu(Medpt)(O2NO)2 (V)”

El-Subruiti, G. M.; Chehata, A. Z.; Massoud, S. S. Int. J. Chem. Kinetics 2002, 34, 1-6.
“Influence of Solvent Structure on the Aquation of Chloro(diethylenetriamine)(ethylenediamine)cobalt(III) Ion in Water and Mixed Aqueous Solvents”

Wen, R.; Massoud, S. S.; Bernal, I. J. Coord. Chem. 2001, 53, 249-268. “The Phenomenon of
Conglomerate Crystallization: Part 54. The Crystallization Modes of Five New Complexes
[trans-(3,2,3-tet)Co(III)X2]Y, X = NO2-, CN-, NCS-”

El-Subruiti, G. M.; Massoud, S. S. Transition Met. Chem. 2000, 25, 344-346. “Solvent Effects
on the Initial and Transition States for the Solvolysis of trans-dichlorobis(N-methylethylenediamine)cobalt(III) Complex in Water-Dimethylsulfoxide Mixtures”

Wen, R.; Bernal, I.; Massoud, S. S.; Thalji, R. K.; Billodeaux; Fronczek, F. R. Inorg. Chim. Acta
1999, 295, 91-105. “Crystal Structures and Magnetic Studies of Six New Nickel (II) Amine Oxalato Compounds”.

Bernal, I.; Cai, J.; Somoza, F.; Massoud, S. S. J. Coord.Chem. 1999, 46, 533-550. “The
Phenomenon of Conglomerate Crystallization. Part 50. The Crystallization Behavior of [transCo(en)2(NO2)2]ClO4 (I), Meso-[trans-Co(N-Me-ethylenediamine)2(NO2)2]ClO4 (II), K[transCo(-alaninato)2(NO2)2] (III) and the Isolation and Partial Structure Description of (H5O2)[transCo(-alaninato)2(NO2)2] (IV)”

Massoud, S. S.; Mautner, F. A.; Abu-Youssef, M.; Shuaib, N. M. Polyhedron 1999, 18, 20612067. “Synthesis and Characterization of Binuclear and Polymeric Five-Coordinate Copper(II)
Complexes Derived from 3,3`,3``-Triaminotripropylamine Ligand (trpn). Crystal Structure of
[Cu(trpn)(N3)]ClO4 (I) and [Cu2(tern)(trpn)(NO2)(H2O)](ClO4)3 (II)”.

El-Sayed, L.; Iskander, M. F.; Hawash, N. M.; Massoud, S. S. Polyhedron 1998, 17, 199.
“Synthesis and Characterization of Nickel(II), Zinc(II), Copper(II), Cobalt(II) and Cobalt(III)
Complexes of -Dicarbonylbis(aroylhydrazone)”.

Massoud, S. S. Transition Met. Chem. 1997, 22, 304-308. “Kinetics and Mechanism of
Decarboxylation of cis-Carbonato- and Bicarbonato(3,3`,3``-triaminotripropylamine)cobalt(III)
Ions”.

Bernal, I.; Somoza, F.; Chen, Y.-C.; Massoud, S. S. J. Coord. Chem. 1997, 41, 233-247. “The
Phenomenon of Conglomerate Crystallization. Part 48. Two Polymorphs of Racemic trans[Co(2,3,2-tet)(NO2)2]NO3 (I and II)”.

Bernal, I.; Cai, J.; Massoud, S. S.; Watkins, S. F.; Fronczek, F. J. Coord. Chem. 1996, 38, 165
181. “The Phenomenon of Kryptoracemic Crystallization. Part 1: Counterion Control of
Crystallization Pathway Selection.
Part 4: The Crystallization Behavior of (+/-)[Co(tren)(NO2)2]Br (I), (+/-)-[Co(tren)(NO2)2]2Br- (ClO4).H2O (II), (+/-)-[Co(tren)(NO2)2]ClO4
(III) and Attempts to Solve the Stucture of (+/-)-[Co(tren)- (NO2)2]NO3 (IV)”.

Bernal, I.; Cetrullo, J.; Cai, J.; Massoud, S. S. Structural Chemistry 1995, 6, 99-113. “The
Phenomenon of Conglomerate Crystallization. Part 40: The Crystallization Behavior of TransCobalt(III) Amines. (+)546- trans-[Co(3,2,3-tet)(NO2)2]Cl.3H2O (I), (-)589-trans-[Co(3,2,3tet)Cl2]NO3 (II) and of (+)546-trans-[Co(3,2,3-tet)(NO2)2]NO3 (III)”.

Sigel, H.; Massoud, S. S.; Corfù, N. A. J. Am. Chem. Soc. 1994, 116, 2958-2971. “Comparison
of the Extent of Base Backbinding in Complexes of Divalent Metal Ions with Guanine (GMP 2-),
Inosine (IMP2-) and Adenosine 5`-Monophosphate (AMP2-). The Crucial Role of N-7 Basicity in
Metal Ion-Nucleic Base Recognition”.

Massoud, S. S. J. Inorg. Biochem. 1994, 55, 183-191. “Adenosine 5`-Triphosphate (ATP)
Hydrolysis Promoted by Aqua-Amine-Cobalt(III) Complexes. Patterns of Reactivity”.

Massoud, S. S. Polyhedron 1994, 13, 3127. “Spectroscopic Characterization for the Geometrical
Isomers of Azido-Amine-Cobalt(III) Complexes”.

Massoud, S. S.; Jordan, R. B. Inorg. Chim. Acta 1994, 221, 9-15. “The Steric Effect on the Ring
Opening Process of the Decaboxylation of Carbonatobis(diamine)cobalt(III) Ions”.
MEETINGS:
Massoud, S. S.; Mautner, F. A.; Vicente, R.; Sweeny, H. N. 231st ACS National Meeting, Atlanta, GA, March 2630, 2006, submitted “Dinuclear Terephthalato-Bridged Copper(II) and Nickel(II) Complexes”.
Massoud, S. S.; Hoang, T.; Mautner, F. A., 229th ACS National Meeting, San Diego, CA, March 13-17, 708,
2005. “Bridged Azido and Thiocyanato Dinuclear Copper(II) Complexes Derived from
Diethyldiethylenetriamine”.
Mautner, F. A.; Massoud, S. S.; Escuer, A.; Vicente, V.; R., Austrian Physical Society Meeting, Vienna, Austria,
Sept. 28-30, 2005. “Terephthalato-Bridged Magnetic Systems”.
Massoud, S. S.; Mukhopadhyay, U.; Bernal, I.; Mautner, F. A., 227th ACS National Meeting, Anaheim, CA,
March 28-April 1, 617, 2004. “Cu(II) Complexes of Tris[(2-pyridyl)methyl]amine: [Cu{N(CH2-py)3}X]ClO4 (X
= N3-, NO2-, NCS-)”.
Massoud, S. S.; Bernal, I.; Mukhopadhyay, U.; Mautner, F. A.; Vicente, V.; R.; Escuer, A., Austrian Physical
Society Meeting, Linz, Austria, Sept. 28-30, 2004. “Transition Metal Complexes with Aminated Ligands”.
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