{"id":{"repo_id":"mit","oai_identifier":"oai:dspace.mit.edu:1721.1/154250"},"canonical_url":"https://search.dev.ndltd.org/etd/mit/oai:dspace.mit.edu:1721.1/154250","repository":{"repo_id":"mit","name":"MIT","base_url":"https://dspace.mit.edu/oai/request"},"display":{"title":"Metal complexes as models for vitamin B₆ catalysis","abstract":"Chapter I. Historical introduction to Vitamin B₆ Complexes. Chapter II. The aldimine complexes N(Salicylidene)glycinato and valinatozinc(II), N,~pyridoxylidene)valinatocopper(II) monohydrate and N-(3-Hydroxypyridyl-2-methylene)valinatocopper( II) hemihydrate have been prepared from L̳-valine. Synthetic methods and characterization data are given. Also prepared were the bis-chelate amino acid ester complexes, Bis[N- (2-ethoxycarbonyl-l-propyl)salicylaldiminato]copper(II) and Bis[N-(3-ethoxycarbonyl-2-propyl)salicylaldiminato]copper(II). The inertness of these two complexes to H-D exchange contrasts with the ready exchange in the absence of base of the complexes derived from a-amino acids. This result shows that facile exchange and racemization properties of Bis[N-(alkoxycarbonylalkyl)salicylaldimino] metal(II) complexes derive principally from the direct attachment of the electron-withdrawing HC=NM and COOC₂H₅ groups to the asymmetric center. The base-catalyzed racemization rates of four copper(II)-aldimine complexes in 95% ethanol at 50° were found to increase in the order N-Salicylidene-L̳-valinatocopper( II), Cu(sal-L̳-val) << N-Pyridoxylidene-L̳-valinatocopper(II) </- N-3-Hydroxypyridyl-2-methylene-L̳-valinatocopper(II) <N-4-NO₂ - Salicylidene-L̳-valinatocopper(II). This order is essentially the same as that of qualitative catalytic effectiveness of the constituent o̲-hydroxyarylcarbonyl compounds in nonenzyrnatic transamination and reinforces in semiquantitative fashion the prevailing model of ligand electronic features requisite to catalytic activity of these compounds.","abstract_html":"Chapter I. Historical introduction to Vitamin B₆ Complexes. Chapter II. The aldimine complexes N(Salicylidene)glycinato and valinatozinc(II), N,~pyridoxylidene)valinatocopper(II) monohydrate and N-(3-Hydroxypyridyl-2-methylene)valinatocopper( II) hemihydrate have been prepared from L̳-valine. Synthetic methods and characterization data are given. Also prepared were the bis-chelate amino acid ester complexes, Bis[N- (2-ethoxycarbonyl-l-propyl)salicylaldiminato]copper(II) and Bis[N-(3-ethoxycarbonyl-2-propyl)salicylaldiminato]copper(II). The inertness of these two complexes to H-D exchange contrasts with the ready exchange in the absence of base of the complexes derived from a-amino acids. This result shows that facile exchange and racemization properties of Bis[N-(alkoxycarbonylalkyl)salicylaldimino] metal(II) complexes derive principally from the direct attachment of the electron-withdrawing HC=NM and COOC₂H₅ groups to the asymmetric center. The base-catalyzed racemization rates of four copper(II)-aldimine complexes in 95% ethanol at 50° were found to increase in the order N-Salicylidene-L̳-valinatocopper( II), Cu(sal-L̳-val) &lt;&lt; N-Pyridoxylidene-L̳-valinatocopper(II) &lt;/- N-3-Hydroxypyridyl-2-methylene-L̳-valinatocopper(II) &lt;N-4-NO₂ - Salicylidene-L̳-valinatocopper(II). This order is essentially the same as that of qualitative catalytic effectiveness of the constituent o̲-hydroxyarylcarbonyl compounds in nonenzyrnatic transamination and reinforces in semiquantitative fashion the prevailing model of ligand electronic features requisite to catalytic activity of these compounds.","abstract_has_math":false,"creators":["Weinstein, Georgia Nan."],"institution":"Massachusetts Institute of Technology","degree_name":"Master","degree_level":null,"degree_discipline":null,"degree_department":"Massachusetts Institute of Technology. Department of Nutrition and Food Science","school":null,"contributors":[],"advisors":["Sanford Miller."],"committee_chairs":[],"committee_members":[],"year":1972,"date_issued":"1972","date_published":"1972","updated_at":"2026-07-22T22:21:17Z","subjects":["Nutrition and Food Science."],"languages":["eng"],"rights":["MIT theses may be protected by copyright. Please reuse MIT thesis content according to the MIT Libraries Permissions Policy, which is available through the URL provided."],"rights_urls":["http://dspace.mit.edu/handle/1721.1/7582"],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/1721.1/154250","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Sanford Miller."]},{"key":"dc:contributor.department","label":"Department","values":["Massachusetts Institute of Technology. Department of Nutrition and Food Science"]},{"key":"dc:contributor.other","label":"Dc Contributor Other","values":["Massachusetts Institute of Technology. Department of Nutrition and Food Science."]},{"key":"dc:creator","label":"Author","values":["Weinstein, Georgia Nan."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2024-04-19T16:26:27Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2024-04-19T16:26:27Z"]},{"key":"dc:date.issued","label":"Date","values":["1972"]},{"key":"dc:publisher","label":"Institution","values":["Massachusetts Institute of Technology"]},{"key":"dc:type","label":"Dc Type","values":["Academic theses.","Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Nutrition and Food Science."]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["MIT theses may be protected by copyright. Please reuse MIT thesis content according to the MIT Libraries Permissions Policy, which is available through the URL provided."]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://dspace.mit.edu/handle/1721.1/7582"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://hdl.handle.net/1721.1/154250"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Thesis: M.S., Massachusetts Institute of Technology, Department of Nutrition and Food Science, 1972","Cataloged from the official PDF version of thesis. Vita.","Includes bibliographical references (pages 58-62)."]},{"key":"dc:description.abstract","label":"Abstract","values":["Chapter I. Historical introduction to Vitamin B₆ Complexes. Chapter II. The aldimine complexes N(Salicylidene)glycinato and valinatozinc(II), N,~pyridoxylidene)valinatocopper(II) monohydrate and N-(3-Hydroxypyridyl-2-methylene)valinatocopper( II) hemihydrate have been prepared from L̳-valine. Synthetic methods and characterization data are given. Also prepared were the bis-chelate amino acid ester complexes, Bis[N- (2-ethoxycarbonyl-l-propyl)salicylaldiminato]copper(II) and Bis[N-(3-ethoxycarbonyl-2-propyl)salicylaldiminato]copper(II). The inertness of these two complexes to H-D exchange contrasts with the ready exchange in the absence of base of the complexes derived from a-amino acids. This result shows that facile exchange and racemization properties of Bis[N-(alkoxycarbonylalkyl)salicylaldimino] metal(II) complexes derive principally from the direct attachment of the electron-withdrawing HC=NM and COOC₂H₅ groups to the asymmetric center. The base-catalyzed racemization rates of four copper(II)-aldimine complexes in 95% ethanol at 50° were found to increase in the order N-Salicylidene-L̳-valinatocopper( II), Cu(sal-L̳-val) << N-Pyridoxylidene-L̳-valinatocopper(II) </- N-3-Hydroxypyridyl-2-methylene-L̳-valinatocopper(II) <N-4-NO₂ - Salicylidene-L̳-valinatocopper(II). This order is essentially the same as that of qualitative catalytic effectiveness of the constituent o̲-hydroxyarylcarbonyl compounds in nonenzyrnatic transamination and reinforces in semiquantitative fashion the prevailing model of ligand electronic features requisite to catalytic activity of these compounds."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["M.S."]},{"key":"dc:title","label":"Title","values":["Metal complexes as models for vitamin B₆ catalysis"]}]}],"canonical_facts":{"dc:contributor.advisor":["Sanford Miller."],"dc:contributor.department":["Massachusetts Institute of Technology. Department of Nutrition and Food Science"],"dc:contributor.other":["Massachusetts Institute of Technology. Department of Nutrition and Food Science."],"dc:creator":["Weinstein, Georgia Nan."],"dc:date.accessioned":["2024-04-19T16:26:27Z"],"dc:date.available":["2024-04-19T16:26:27Z"],"dc:date.issued":["1972"],"dc:description":["Thesis: M.S., Massachusetts Institute of Technology, Department of Nutrition and Food Science, 1972","Cataloged from the official PDF version of thesis. Vita.","Includes bibliographical references (pages 58-62)."],"dc:description.abstract":["Chapter I. Historical introduction to Vitamin B₆ Complexes. Chapter II. The aldimine complexes N(Salicylidene)glycinato and valinatozinc(II), N,~pyridoxylidene)valinatocopper(II) monohydrate and N-(3-Hydroxypyridyl-2-methylene)valinatocopper( II) hemihydrate have been prepared from L̳-valine. Synthetic methods and characterization data are given. Also prepared were the bis-chelate amino acid ester complexes, Bis[N- (2-ethoxycarbonyl-l-propyl)salicylaldiminato]copper(II) and Bis[N-(3-ethoxycarbonyl-2-propyl)salicylaldiminato]copper(II). The inertness of these two complexes to H-D exchange contrasts with the ready exchange in the absence of base of the complexes derived from a-amino acids. This result shows that facile exchange and racemization properties of Bis[N-(alkoxycarbonylalkyl)salicylaldimino] metal(II) complexes derive principally from the direct attachment of the electron-withdrawing HC=NM and COOC₂H₅ groups to the asymmetric center. The base-catalyzed racemization rates of four copper(II)-aldimine complexes in 95% ethanol at 50° were found to increase in the order N-Salicylidene-L̳-valinatocopper( II), Cu(sal-L̳-val) << N-Pyridoxylidene-L̳-valinatocopper(II) </- N-3-Hydroxypyridyl-2-methylene-L̳-valinatocopper(II) <N-4-NO₂ - Salicylidene-L̳-valinatocopper(II). This order is essentially the same as that of qualitative catalytic effectiveness of the constituent o̲-hydroxyarylcarbonyl compounds in nonenzyrnatic transamination and reinforces in semiquantitative fashion the prevailing model of ligand electronic features requisite to catalytic activity of these compounds."],"dc:description.degree":["M.S."],"dc:identifier.uri":["https://hdl.handle.net/1721.1/154250"],"dc:language.iso":["eng"],"dc:publisher":["Massachusetts Institute of Technology"],"dc:rights":["MIT theses may be protected by copyright. Please reuse MIT thesis content according to the MIT Libraries Permissions Policy, which is available through the URL provided."],"dc:rights.uri":["http://dspace.mit.edu/handle/1721.1/7582"],"dc:subject":["Nutrition and Food Science."],"dc:title":["Metal complexes as models for vitamin B₆ catalysis"],"dc:type":["Academic theses.","Thesis"],"thesis:degree_name":["Master"]},"updated_at":"2026-07-22T22:21:17Z"}