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Dr. Changamu Evans Ogwagwa

Lecturer, Department of Chemistry

Home School of Pure & Applied Sciences Department of Chemistry Dr. Changamu Evans Ogwagwa

Dr. Changamu Evans Ogwagwa

Lecturer, Department of Chemistry

Refereed Journal Articles

  1. Evans O. Changamu, Holger B. Friedrich, Manuel A. Fernandes, 2009. A structural investigation of the heterobimetallic carbocation complex [Cp*(CO) 2 Fe{-CH 2 CH(CH 2 ) 3 }W(CO) 3 Cp]BPh 4 Inorganica Chimica Acta 362, 2947–2950. DOI: 10.1016/j.ica.2008.12.026
  2. O. Changamu, H.B. Friedrich, M. Rademeyer, 2008. Synthesis and structure of the monometallic cationic complex [Cp(CO) 2 Fe { 2 -(CH 2 CHCH 2 CH 3 )}]PF 6 (Cp= 5 -C 5 H 5 ), Journal of Organometallic Chemistry 693 (1), 164-168
  3. O. Changamu , H.B. Friedrich, 2008. Synthesis, characterization and reactions of the transition metal halogenoalkyl carbocation complexes [Cp (CO) 2 M{ 2 -CH 2 CH(CH 2 ) n X}]PF 6 (n= 1–8, 10, M= Fe; n= 3, 4 M= Ru; X), Journal of Organometallic Chemistry 693 (21-22), 3351-3356
  4. O. Changamu , HB Friedrich, RA Howie, M Rademeyer, 2007. A structural investigation of the carbocation complex [{Cp(CO) 2 Fe} 2 {-(C 3 H 5 )}]PF 6 Journal of Organometallic Chemistry 692 (22), 5091-5096
  5. Evans O. Changamu , Holger B. Friedrich, 2007. A study of b-hydride abstraction from alkanediyl homobimetallic complexes [{Cp(CO) 2 Fe} 2 {-(C n H 2n )}] (n = 4-10, Cp= 5 -C 5 H 5 ) Journal of Organometallic Chemistry Volume 692, Issue 5, 1, 1138-1149, https://doi.org/10.1016/j.jorganchem.2006.11.017
  6. Evans O. Changamu , Holger B. Friedrich, Melanie Rademeyer, 2007. Synthesis and characterization of transition metal stabilized carbocations of the types [Cp(CO)2Fe{-(C n H 2n 1 }M(CO) x Cp]PF 6 (x = 2, M = Fe or Ru; x = 3, M = W, Cp = 5 -C 5 (CH 3 ) 5 ; Cp = 5 -C 5 H 5 ; n = 3–6) and [Cp(CO) 2 Ru{-(CnH 2n 1 )}W(CO) 3 Cp]PF 6 (n = 3–5) and the crystal structures of the complexes [Cp(CO) 2 Fe(CH 2 ) 3 Ru(CO) 2 Cp], [Cp(CO) 2 Fe(CH 2 ) 5 Ru(CO) 2 Cp], [Cp(CO) 2 Fe-(CH 2 ) 5 W(CO) 3 Cp], and [Cp(CO) 2 Ru(CH 2 ) 5 W(CO) 3 Cp]; Journal of Organometallic Chemistry Volume 692, Issue 12, 15 2456-2472, https://doi.org/10.1016/j.jorganchem.2007.02.016
  7. O. Changamu , H.B. Friedrich, M.O. Onani, M. Rademeyer, 2006. Reaction studies on some functionalized alkyl transition metal compounds and the crystal structure of [Cp(CO) 3 W{(CH 2 ) 3 NO 2 }], Journal of organometallic chemistry 691 (22), 4615-4625
  8. B. Friedrich, E.O. Changamu , M. Rademeyer, 2006. [-1C1:2 (C2, C3-)-Allyl] tetracarbonyl-1 2 C, 2 2 C-(1 5 -cyclopentadienyl)(2 5 -pentamethylcyclopentadienyl) rutheniumiron hexafluorophosphate, Acta Crystallographica Section E: Structure Reports Online 62 (3), m405-m407
  9. O. Changamu , H.B. Friedrich, M. Rademeyer, 2006. [-1C1: 2 (C2, C3-)-Allyl] tetracarbonyl-1 2 C, 2 2 C-(1 5 -cyclopentadienyl)(2 5 -pentamethylcyclopentadienyl) diiron (II) hexafluorophosphate, Acta Crystallographica Section E: Structure Reports Online 62 (3), m442-m444; DOI: 10.1107/S1600536806003503
  10. Adamu Abdulhameed, Harun M. Mbuvi*, Evans O. Changamu , 2020. Synthesis of Cellulose-Based Superabsorbent Hydrogel from Rice Husk Using a Microwave, American Journal of Materials Science, 10(1): 1-8; DOI:10.5923/j.materials.20201001.01
  11. Mariah Onditi,* Geoffrey Bosire, Evans Changamu , and Catherine Ngila, 2019. Degradation of Rhodamine B Dye by Cactus Polysaccharide-Synthesized Silver Nanoparticles Monitored by Fluorescence Excitation-Emission Matrix (FEEM) Spectroscopy, Starch - Stärke, 71, 1800127; DOI: 10.1002/star.201800127
  12. Rozy Munene, Evans Changamu , Nicholas Korir and Gweyi-Onyango Joseph, 2017. Effects of different nitrogen forms on growth, phenolics, flavonoids and antioxidant activity in amaranth species. Tropical Plant Research, 4(1): 81–89
  13. Munene, E. Changamu , N Korir, JP Gweyi-Onyango, 2017. Differential Impact of Nitrogen Forms on Selected Phytochemicals and Oxalate Contents in Three Vegetable Amaranth Varieties in Kenya. Annals, Food Science and Technology 18 (2), 238-256
  14. Munene Rozy, Changamu Evans , Korir Nicholas and P. Gweyi-Onyango Joseph, 2016. Characterization and Documentation of Factors Contributing to Production and Consumption of African Leafy Vegetables (ALVs) in Kiambu and Kirinyaga Counties in Kenya. Asian Research Journal of Agriculture 1(3), 1-9
  15. Mariah Onditi, Adedeji A. Adelodun, Evans O. Changamu , Jane C. Ngila, 2016. Removal of Pb 2+ and Cd 2+ from drinking water using polysaccharide extract isolated from cactus pads (Opuntia ficus indica). Journal of Applied Polymer Science 133(38), 43913, DOI: 10.1002/app.43913
  16. Stanslaus M. Lusambili, Alphonse W. Wafula, Evans C. Ogwagwa , 2016. Spectroscopic and physical characterization of clays from Ilesi area in Kakamega County and their suitability for pottery, Journal of the Kenya Chemical Society 9, 1-14
  17. Cyprian M. M’Thiruaine, Holger B. Friedrich, Bernard Omondi, Evans O. Changamu , 2013. A Structural Investigation of the D 2 O Solvated, Acetone Solvated and Non-solvated 1,4-Diazabicyclo[2.2.2] octane Complexes of the Half Sandwich Moiety [(h 5 -C 5 H 5 )(CO) 2 Fe]. South African Journal Chemistry, 66, 237 – 243;
  18. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu , Bernard Omondi, 2012. Regioselective reactions of electrophilic iron dicarbonyl cations, [(h 5 -C 5 R 5 )(CO) 2 Fe] + (R = H, CH 3 ) with heterofunctional amine ligands. Journal of Organometallic Chemistry 717, 52-60; DOI: 10.1016/j.jorganchem.2012.06.034
  19. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu , Bernard Omondi, 2012. Syntheses, structural elucidation and reactions of allylamino compounds of the type, [h 5 - C 5 R 5 (CO) 2 Fe(NH 2 CH 2 CH=CH 2 )]BF 4 , Polyhedron 40 81–92; DOI:10.1016/j.poly.2012.03.039
  20. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Manuel Fernandes, 2012. Dicarbonyl(hexamethylene-1,3,5,7-tetramine-N 1 )(5-pentamethylcyclopentadienyl) iron(II) tetrafluoridoborate, Acta Crystallographica E68, m931; DOI:10.1107/S1600536812026360
  21. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Manuel Fernandes, 2012. Dicarbonyl( 5 -cyclopentadienyl)(hexamethylene-1,3,5,7-tetramine-N1)iron(II) tetrafluoridoborate, Acta Crystallographica E68, m1077; https://doi.org/10.1107/S1600536812031649
  22. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Muhammad D. Bala, 2012. Reactions of N-heterocyclic ligands with substitutionally labile organometallic complexes, [(h 5 -C 5 R 5 )Fe(CO) 2 E]BF 4 Inorganica Chimica Acta 390, 83–94; DOI: 10.1016/j.ica.2012.04.003
  23. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Muhammad D. Bala, 2012. Synthesis, characterization and structural elucidation of water-soluble 1-aminoalkane and ,-diaminoalkane complexes of the pentamethylcyclopentadienyliron dicarbonyl cation, [Cp*(CO) 2 Fe] + Inorganica Chimica Acta, 382, 27–34; DOI:10.1016/j.ica.2011.09.058
  24. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Manuel A. Fernandes, 2012. Dicarbonyl(h 5 -cyclopentadienyl)(2,3-dibromopropanamine-N)iron(II) tetrafluoridoborate, Acta Crystallographica, E68, m932; DOI:10.1107/S1600536812026925
  25. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Bernard Omondi, 2011. (-Formato-2O:O)bis[dicarbonyl( 5 -cyclopentadienyl)iron(II)] tetrafluoridoborate, Acta Crystallographica, E67 m1252; DOI:10.1107/S1600536811032764
  26. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Muhammad D. Bala, 2011. Acetonitriledicarbonyl(h 5 -pentamethyl-cyclopentadienyl)iron(II) tetrafluoridoborate Acta Crystallographica, Section E67 m924. DOI:10.1107/S1600536811021350
  27. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Muhammad D. Bala, 2011. Synthesis and characterization of amine complexes of the cyclopentadienyliron dicarbonyl complex cation, [Cp(CO) 2 Fe] + Inorganica Chimica Acta 366, 105-115. DOI:10.1016/j.ica.2010.10.018
  28. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Bernard Omondi, 2011. (-Ethane-1,2-diamine-2N:N)bis[dicarbonyl( 5 -cyclopentadienyl)iron(II)]bis (tetrafluoridoborate) Acta Crystallographica (). E67, m485 DOI: 10.1107/S1600536811010154

Book Chapters

  1. Mariah Onditi, Geoffrey Bosire, Evans Changamu and Catherine Ngila, 2016. Preparation and characterization of polyvinyl alcohol/hemicellulose nanofibers via electrospinning for removal of natural organic matter (NOM) from waste water. The OWSD 5th General Assembly and International Conference in 16-19 May 2 016, Kuwait.
  2. Mariah Onditi, Evans Changamu and Catherine Ngila, 2015. Extraction and characterization of hemicellulose from wild species of cactus plant ( opuntia ficus indica ) with application in water purification Materials, Analytical and Physical Electrochemistry Today (MAPET) 3 rd International Symposium on Electrochemistry ElectrochemSA, SACI Bellville, SOUTH AFRICA 26 - 28 May 2015.
  3. M ariah Onditi, Evans Changamu and Catherine Ngila, 2015. Utilization of cactus hemicellulose based biopolymer for water treatment 3rd Conference on Emerging Frontiers For Sustainable Water: A Trilateral Partnership Africa India UK: Protea Hotel Wanderers , Illovo Johannesburg 3 5 August 2015.
  4. Mariah Onditi, Evans Changamu and Catherine Ngila, 2015. Adsorption of heavy metals from aqueous solution using hemicellulose isolated from cactus plant presented at the 16 th WaterNet/WARFSA/GWP SA Symposium, held in Mauritius on 28 - 30 October 2015
  5. Mariah Onditi, Evans Changamu and Catherine Ngila, 2015. Electrospun Hemicellulose-based Polymer Nanofibers Utilized for Water Treatment presented at the Materials Research Society 2015 Fall Meeting in Nov 29 Dec 4, 2015, in Boston, Massachusetts, USA.
  6. Evans C. Ogwagwa , C. M’thiruaine and H.B. Friedrich, Water-soluble organometallics of biologically relevant metals and ligands, Fifth annual Ghana Biomedical Convention, in Accra Ghana between 30th July– 1st August 2012.
  7. Evans O Changamu, The role of chemistry in industrial development - The contribution of transition metals, a paper presented during the Kenya Chemical Society seminar as part of the International Year of Chemistry Celebrations on 30th April 2011 at Kenyatta University.
  8. Evans O. Changamu, Water-soluble organometallic complexes, paper presented as poster during the monthly poster presentations at Novartis Institutes for Biomedical Research held on 20th August 2010, at Cambridge, Massachusetts, USA.
  9. Evans O. Changamu, Complexes of Organometallic Lewis acids, presented at Harvard University, Department of Chemistry and Chemical biology on 23rd July 2010 USA.
  10. Evans O. Changamu, and Holger B. Friedrich “Synthesis and structure of the cationic heterobimetallic complex [Cp*(CO) 2 Fe{ 2 -CH 2 CH(CH 2 ) 3 }W(CO) 3 Cp]BPh 4 (Cp* = 5 -C 5 (CH 3 ) 5 ; Cp = 5 -C 5 H 5 )”, paper presented as poster during the 38th International Conferences on Coordination Chemistry held between 20 – 25 July, 2008 at Renaissance Hotel, Jerusalem (Israel)
  11. Evans O. Changamu, and Holger B. Friedrich, 2007. Synthesis and Characterization of Some Transition Metal-Stabilised Carbocations, SACI Conference on Inorganic Chemistry (INORG 007) held at Club Mykonos, July 2007.

Conference Papers

  1. Adamu Abdulhameed, Harun M. Mbuvi*, Evans O. Changamu , 2020. Synthesis of Cellulose-Based Superabsorbent Hydrogel from Rice Husk Using a Microwave, American Journal of Materials Science, 10(1): 1-8; DOI:10.5923/j.materials.20201001.01
  2. Mariah Onditi,* Geoffrey Bosire, Evans Changamu , and Catherine Ngila, 2019. Degradation of Rhodamine B Dye by Cactus Polysaccharide-Synthesized Silver Nanoparticles Monitored by Fluorescence Excitation-Emission Matrix (FEEM) Spectroscopy, Starch - Stärke, 71, 1800127; DOI: 10.1002/star.201800127
  3. Rozy Munene, Evans Changamu , Nicholas Korir and Gweyi-Onyango Joseph, 2017. Effects of different nitrogen forms on growth, phenolics, flavonoids and antioxidant activity in amaranth species. Tropical Plant Research, 4(1): 81–89
  4. Munene, E. Changamu , N Korir, JP Gweyi-Onyango, 2017. Differential Impact of Nitrogen Forms on Selected Phytochemicals and Oxalate Contents in Three Vegetable Amaranth Varieties in Kenya. Annals, Food Science and Technology 18 (2), 238-256
  5. Munene Rozy, Changamu Evans , Korir Nicholas and P. Gweyi-Onyango Joseph, 2016. Characterization and Documentation of Factors Contributing to Production and Consumption of African Leafy Vegetables (ALVs) in Kiambu and Kirinyaga Counties in Kenya. Asian Research Journal of Agriculture 1(3), 1-9
  6. Mariah Onditi, Adedeji A. Adelodun, Evans O. Changamu , Jane C. Ngila, 2016. Removal of Pb 2+ and Cd 2+ from drinking water using polysaccharide extract isolated from cactus pads (Opuntia ficus indica). Journal of Applied Polymer Science 133(38), 43913, DOI: 10.1002/app.43913
  7. Stanslaus M. Lusambili, Alphonse W. Wafula, Evans C. Ogwagwa , 2016. Spectroscopic and physical characterization of clays from Ilesi area in Kakamega County and their suitability for pottery, Journal of the Kenya Chemical Society 9, 1-14
  8. Cyprian M. M’Thiruaine, Holger B. Friedrich, Bernard Omondi, Evans O. Changamu , 2013. A Structural Investigation of the D 2 O Solvated, Acetone Solvated and Non-solvated 1,4-Diazabicyclo[2.2.2] octane Complexes of the Half Sandwich Moiety [(h 5 -C 5 H 5 )(CO) 2 Fe]. South African Journal Chemistry, 66, 237 – 243;
  9. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu , Bernard Omondi, 2012. Regioselective reactions of electrophilic iron dicarbonyl cations, [(h 5 -C 5 R 5 )(CO) 2 Fe] + (R = H, CH 3 ) with heterofunctional amine ligands. Journal of Organometallic Chemistry 717, 52-60; DOI: 10.1016/j.jorganchem.2012.06.034
  10. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu , Bernard Omondi, 2012. Syntheses, structural elucidation and reactions of allylamino compounds of the type, [h 5 - C 5 R 5 (CO) 2 Fe(NH 2 CH 2 CH=CH 2 )]BF 4 , Polyhedron 40 81–92; DOI:10.1016/j.poly.2012.03.039
  11. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Manuel Fernandes, 2012. Dicarbonyl(hexamethylene-1,3,5,7-tetramine-N 1 )(5-pentamethylcyclopentadienyl) iron(II) tetrafluoridoborate, Acta Crystallographica E68, m931; DOI:10.1107/S1600536812026360
  12. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Manuel Fernandes, 2012. Dicarbonyl( 5 -cyclopentadienyl)(hexamethylene-1,3,5,7-tetramine-N1)iron(II) tetrafluoridoborate, Acta Crystallographica E68, m1077; https://doi.org/10.1107/S1600536812031649
  13. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Muhammad D. Bala, 2012. Reactions of N-heterocyclic ligands with substitutionally labile organometallic complexes, [(h 5 -C 5 R 5 )Fe(CO) 2 E]BF 4 Inorganica Chimica Acta 390, 83–94; DOI: 10.1016/j.ica.2012.04.003
  14. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Muhammad D. Bala, 2012. Synthesis, characterization and structural elucidation of water-soluble 1-aminoalkane and ,-diaminoalkane complexes of the pentamethylcyclopentadienyliron dicarbonyl cation, [Cp*(CO) 2 Fe] + Inorganica Chimica Acta, 382, 27–34; DOI:10.1016/j.ica.2011.09.058
  15. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Manuel A. Fernandes, 2012. Dicarbonyl(h 5 -cyclopentadienyl)(2,3-dibromopropanamine-N)iron(II) tetrafluoridoborate, Acta Crystallographica, E68, m932; DOI:10.1107/S1600536812026925
  16. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Bernard Omondi, 2011. (-Formato-2O:O)bis[dicarbonyl( 5 -cyclopentadienyl)iron(II)] tetrafluoridoborate, Acta Crystallographica, E67 m1252; DOI:10.1107/S1600536811032764
  17. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Muhammad D. Bala, 2011. Acetonitriledicarbonyl(h 5 -pentamethyl-cyclopentadienyl)iron(II) tetrafluoridoborate Acta Crystallographica, Section E67 m924. DOI:10.1107/S1600536811021350
  18. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Muhammad D. Bala, 2011. Synthesis and characterization of amine complexes of the cyclopentadienyliron dicarbonyl complex cation, [Cp(CO) 2 Fe] + Inorganica Chimica Acta 366, 105-115. DOI:10.1016/j.ica.2010.10.018
  19. Cyprian M. M’thiruaine, Holger B. Friedrich, Evans O. Changamu and Bernard Omondi, 2011. (-Ethane-1,2-diamine-2N:N)bis[dicarbonyl( 5 -cyclopentadienyl)iron(II)]bis (tetrafluoridoborate) Acta Crystallographica (). E67, m485 DOI: 10.1107/S1600536811010154