{"id":{"repo_id":"sask","oai_identifier":"oai:harvest.usask.ca:10388/etd-05222007-104556"},"canonical_url":"https://search.dev.ndltd.org/etd/sask/oai:harvest.usask.ca:10388/etd-05222007-104556","repository":{"repo_id":"sask","name":"University of Saskatchewan","base_url":"https://harvest.usask.ca/server/oai/request"},"display":{"title":"Electrochemical detection of chemical warfare agents","abstract":"tert-butyl 1’-methoxycarbonyl-1-ferrocenecarbamate, Boc-NH-Fc-COOMe, (1) was synthesized according to the literature procedure and modified to 1-amino-n′-ferrocenemethylcarboxylate, 1,n′-H₂N-Fc-COOCH₃ (2) by removing the Boc-group with TFA/Et₃N mixture in dichloromethane. Compound 2 reacted with alkylating agents like MeI, EtI, EtSCH₂CH₂Cl (MA) and (CN)(EtO)₂P(O) (NA) to form MeNH-Fc-COOMe (3), EtNH-Fc-COOMe (4), EtSCH₂CH₂NH-Fc-COOMe (5), (EtO)₂P(O)NH-Fc-COOMe (6), respectively. Cyclic voltammetry (CV) of these compounds showed different half-wave potential characteristics compared to aminoferrocene and was dependent on the nature of the substituents, which was rationalized by molecular orbital calculations. Electron donating groups (Me, Et and 2-chloroethyl ethylsulfide, MA) shifted the half-wave potential towards the cathodic direction while electron withdrawing group like diethyl cyanophosphonate, NA, shifted it toward anodic direction. Anodic to cathodic peak separation were found to be within 62-88 mV indicating a quasi-reversible system. Hydrolysis of compound 1 resulted in the formation of tert-butyl 1’-methoxycarbonyl-1-ferrocenecarboxylic acid, Boc-NH-Fc-COOH, (11) which was coupled with cystamine using the EDC/HOBt protocol to synthesize the cystamine conjugate [BocHN-Fc-CO-CSA]₂ (12). This molecule is equipped with an amino group that directly linked to the redox receptor. Compound 12 was fully characterized by spectroscopic methods and by single crystal x-ray diffraction. The cystamine conjugate 12 formed films on gold substrates, which upon deprotection of the amino group, reacted with chemical warfare agents (CWAs) mimics, such as EtSCH₂CH₂Cl (MA), a simulant for the sulfur mustard HD, and (CN)(EtO)₂P(O) (NA), a simulant for the nerve agent Tabun. Their reaction with the surface-bound ferrocene derivative results in the formation of N-substituted products. CV measurements showed anodic shifts of the Fc redox potentials by 50 (±5) mV after exposure to MA, and NA. Measurements by quartz crystal microbalance (QCM) showed an increase in mass upon exposure to MA and NA. Ellipsometry measured a film thickness increase from 6 (±1) Å for the deprotected film to 10 (±4) Å for the film modified with MA and to 7 (±2) Å for the film modified with NA. The surfaces were analyzed by x-ray photoelectron spectroscopy (XPS) and clearly showed the attachment of the cystamine conjugate on the surface and its reaction with CWAs mimics.","abstract_html":"tert-butyl 1’-methoxycarbonyl-1-ferrocenecarbamate, Boc-NH-Fc-COOMe, (1) was synthesized according to the literature procedure and modified to 1-amino-n′-ferrocenemethylcarboxylate, 1,n′-H₂N-Fc-COOCH₃ (2) by removing the Boc-group with TFA/Et₃N mixture in dichloromethane. Compound 2 reacted with alkylating agents like MeI, EtI, EtSCH₂CH₂Cl (MA) and (CN)(EtO)₂P(O) (NA) to form MeNH-Fc-COOMe (3), EtNH-Fc-COOMe (4), EtSCH₂CH₂NH-Fc-COOMe (5), (EtO)₂P(O)NH-Fc-COOMe (6), respectively. Cyclic voltammetry (CV) of these compounds showed different half-wave potential characteristics compared to aminoferrocene and was dependent on the nature of the substituents, which was rationalized by molecular orbital calculations. Electron donating groups (Me, Et and 2-chloroethyl ethylsulfide, MA) shifted the half-wave potential towards the cathodic direction while electron withdrawing group like diethyl cyanophosphonate, NA, shifted it toward anodic direction. Anodic to cathodic peak separation were found to be within 62-88 mV indicating a quasi-reversible system. Hydrolysis of compound 1 resulted in the formation of tert-butyl 1’-methoxycarbonyl-1-ferrocenecarboxylic acid, Boc-NH-Fc-COOH, (11) which was coupled with cystamine using the EDC/HOBt protocol to synthesize the cystamine conjugate [BocHN-Fc-CO-CSA]₂ (12). This molecule is equipped with an amino group that directly linked to the redox receptor. Compound 12 was fully characterized by spectroscopic methods and by single crystal x-ray diffraction. The cystamine conjugate 12 formed films on gold substrates, which upon deprotection of the amino group, reacted with chemical warfare agents (CWAs) mimics, such as EtSCH₂CH₂Cl (MA), a simulant for the sulfur mustard HD, and (CN)(EtO)₂P(O) (NA), a simulant for the nerve agent Tabun. Their reaction with the surface-bound ferrocene derivative results in the formation of N-substituted products. CV measurements showed anodic shifts of the Fc redox potentials by 50 (±5) mV after exposure to MA, and NA. Measurements by quartz crystal microbalance (QCM) showed an increase in mass upon exposure to MA and NA. Ellipsometry measured a film thickness increase from 6 (±1) Å for the deprotected film to 10 (±4) Å for the film modified with MA and to 7 (±2) Å for the film modified with NA. The surfaces were analyzed by x-ray photoelectron spectroscopy (XPS) and clearly showed the attachment of the cystamine conjugate on the surface and its reaction with CWAs mimics.","abstract_has_math":false,"creators":["Khan, Mohammad Abdul Kader"],"institution":"University of Saskatchewan","degree_name":"Master of Science (M.Sc.)","degree_level":"Masters","degree_discipline":"Chemistry","degree_department":null,"school":null,"contributors":[],"advisors":["Kraatz, Heinz-Bernhard"],"committee_chairs":[],"committee_members":[],"year":2007,"date_issued":"2007-05-22","date_published":"2007-05-22","updated_at":"2026-07-24T04:26:59Z","subjects":["Chemical warfare agents","Electrochemical detection","Cyclic voltammetry"],"languages":["en_US"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/10388/etd-05222007-104556","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Kraatz, Heinz-Bernhard"]},{"key":"dc:creator","label":"Author","values":["Khan, Mohammad Abdul Kader"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2007-05-22T10:45:56Z","2013-01-04T04:31:16Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2007-05-22T08:00:00Z","2013-01-04T04:31:16Z"]},{"key":"dc:date.issued","label":"Date","values":["2007-05-22"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Chemistry"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science (M.Sc.)"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Saskatchewan"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Chemical warfare agents","Electrochemical detection","Cyclic voltammetry"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en_US"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://hdl.handle.net/10388/etd-05222007-104556"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["tert-butyl 1’-methoxycarbonyl-1-ferrocenecarbamate, Boc-NH-Fc-COOMe, (1) was synthesized according to the literature procedure and modified to 1-amino-n′-ferrocenemethylcarboxylate, 1,n′-H₂N-Fc-COOCH₃ (2) by removing the Boc-group with TFA/Et₃N mixture in dichloromethane. Compound 2 reacted with alkylating agents like MeI, EtI, EtSCH₂CH₂Cl (MA) and (CN)(EtO)₂P(O) (NA) to form MeNH-Fc-COOMe (3), EtNH-Fc-COOMe (4), EtSCH₂CH₂NH-Fc-COOMe (5), (EtO)₂P(O)NH-Fc-COOMe (6), respectively. Cyclic voltammetry (CV) of these compounds showed different half-wave potential characteristics compared to aminoferrocene and was dependent on the nature of the substituents, which was rationalized by molecular orbital calculations. Electron donating groups (Me, Et and 2-chloroethyl ethylsulfide, MA) shifted the half-wave potential towards the cathodic direction while electron withdrawing group like diethyl cyanophosphonate, NA, shifted it toward anodic direction. Anodic to cathodic peak separation were found to be within 62-88 mV indicating a quasi-reversible system. Hydrolysis of compound 1 resulted in the formation of tert-butyl 1’-methoxycarbonyl-1-ferrocenecarboxylic acid, Boc-NH-Fc-COOH, (11) which was coupled with cystamine using the EDC/HOBt protocol to synthesize the cystamine conjugate [BocHN-Fc-CO-CSA]₂ (12). This molecule is equipped with an amino group that directly linked to the redox receptor. Compound 12 was fully characterized by spectroscopic methods and by single crystal x-ray diffraction. The cystamine conjugate 12 formed films on gold substrates, which upon deprotection of the amino group, reacted with chemical warfare agents (CWAs) mimics, such as EtSCH₂CH₂Cl (MA), a simulant for the sulfur mustard HD, and (CN)(EtO)₂P(O) (NA), a simulant for the nerve agent Tabun. Their reaction with the surface-bound ferrocene derivative results in the formation of N-substituted products. CV measurements showed anodic shifts of the Fc redox potentials by 50 (±5) mV after exposure to MA, and NA. Measurements by quartz crystal microbalance (QCM) showed an increase in mass upon exposure to MA and NA. Ellipsometry measured a film thickness increase from 6 (±1) Å for the deprotected film to 10 (±4) Å for the film modified with MA and to 7 (±2) Å for the film modified with NA. The surfaces were analyzed by x-ray photoelectron spectroscopy (XPS) and clearly showed the attachment of the cystamine conjugate on the surface and its reaction with CWAs mimics."]},{"key":"dc:title","label":"Title","values":["Electrochemical detection of chemical warfare agents"]}]}],"canonical_facts":{"dc:contributor.advisor":["Kraatz, Heinz-Bernhard"],"dc:creator":["Khan, Mohammad Abdul Kader"],"dc:date.accessioned":["2007-05-22T10:45:56Z","2013-01-04T04:31:16Z"],"dc:date.available":["2007-05-22T08:00:00Z","2013-01-04T04:31:16Z"],"dc:date.issued":["2007-05-22"],"dc:description.abstract":["tert-butyl 1’-methoxycarbonyl-1-ferrocenecarbamate, Boc-NH-Fc-COOMe, (1) was synthesized according to the literature procedure and modified to 1-amino-n′-ferrocenemethylcarboxylate, 1,n′-H₂N-Fc-COOCH₃ (2) by removing the Boc-group with TFA/Et₃N mixture in dichloromethane. Compound 2 reacted with alkylating agents like MeI, EtI, EtSCH₂CH₂Cl (MA) and (CN)(EtO)₂P(O) (NA) to form MeNH-Fc-COOMe (3), EtNH-Fc-COOMe (4), EtSCH₂CH₂NH-Fc-COOMe (5), (EtO)₂P(O)NH-Fc-COOMe (6), respectively. Cyclic voltammetry (CV) of these compounds showed different half-wave potential characteristics compared to aminoferrocene and was dependent on the nature of the substituents, which was rationalized by molecular orbital calculations. Electron donating groups (Me, Et and 2-chloroethyl ethylsulfide, MA) shifted the half-wave potential towards the cathodic direction while electron withdrawing group like diethyl cyanophosphonate, NA, shifted it toward anodic direction. Anodic to cathodic peak separation were found to be within 62-88 mV indicating a quasi-reversible system. Hydrolysis of compound 1 resulted in the formation of tert-butyl 1’-methoxycarbonyl-1-ferrocenecarboxylic acid, Boc-NH-Fc-COOH, (11) which was coupled with cystamine using the EDC/HOBt protocol to synthesize the cystamine conjugate [BocHN-Fc-CO-CSA]₂ (12). This molecule is equipped with an amino group that directly linked to the redox receptor. Compound 12 was fully characterized by spectroscopic methods and by single crystal x-ray diffraction. The cystamine conjugate 12 formed films on gold substrates, which upon deprotection of the amino group, reacted with chemical warfare agents (CWAs) mimics, such as EtSCH₂CH₂Cl (MA), a simulant for the sulfur mustard HD, and (CN)(EtO)₂P(O) (NA), a simulant for the nerve agent Tabun. Their reaction with the surface-bound ferrocene derivative results in the formation of N-substituted products. CV measurements showed anodic shifts of the Fc redox potentials by 50 (±5) mV after exposure to MA, and NA. Measurements by quartz crystal microbalance (QCM) showed an increase in mass upon exposure to MA and NA. Ellipsometry measured a film thickness increase from 6 (±1) Å for the deprotected film to 10 (±4) Å for the film modified with MA and to 7 (±2) Å for the film modified with NA. The surfaces were analyzed by x-ray photoelectron spectroscopy (XPS) and clearly showed the attachment of the cystamine conjugate on the surface and its reaction with CWAs mimics."],"dc:identifier.uri":["https://hdl.handle.net/10388/etd-05222007-104556"],"dc:language.iso":["en_US"],"dc:subject":["Chemical warfare agents","Electrochemical detection","Cyclic voltammetry"],"dc:title":["Electrochemical detection of chemical warfare agents"],"thesis:degree_discipline":["Chemistry"],"thesis:degree_level":["Masters"],"thesis:degree_name":["Master of Science (M.Sc.)"],"thesis:institution_name":["University of Saskatchewan"]},"updated_at":"2026-07-24T04:26:59Z"}