Spontaneous, metal ion- and pyridoxamine-catalyzed decarboxylation of 2-oxalopropionic acid.

Bibliographic Details
Main Author: Kubala, Gregory
Other Authors: Bates, George W. (degree committee member.), Hogg, John L. (degree committee member.)
Format: Thesis Book
Language:English
Published: 1982.
Subjects:
Online Access:Link to ProQuest Copy
Link to OAKTrust copy

MARC

Tag First Indicator Second Indicator Subfields
LEADER 00000ctm a2200000Ia 4500
001 in00000097187
005 20220103135115.0
008 821113s1982 xx a bm 000 0 eng d
035 |9 AAK9064AM 
035 |a (OCoLC)08955184 
035 |a (OCoLC)8955184 
035 |a (OCoLC)ocm08955184 
040 |a TXA  |b eng  |c TXA  |d OCLCQ  |d OCLCF  |d OCLCO  |d OCLCQ  |d UMI  |d TXA 
049 |a TXAM 
099 |a 1982  |a Dissertation  |a K95 
100 1 |a Kubala, Gregory 
245 1 0 |a Spontaneous, metal ion- and pyridoxamine-catalyzed decarboxylation of 2-oxalopropionic acid. 
264 1 |c 1982. 
300 |a xi, 151 leaves :  |b illustrations ;  |c 29 cm 
336 |a text  |b txt  |2 rdacontent 
337 |a unmediated  |b n  |2 rdamedia 
338 |a volume  |b nc  |2 rdacarrier 
500 |a "Major subject: Chemistry." 
500 |a Typescript (photocopy). 
500 |a Vita. 
502 |b Ph. D. in Philosophy  |c Texas A & M University  |d 1982 
504 |a Includes bibliographical references (leaves 143-150). 
520 3 |a The proton association constants for the carboxyl protons of 2-oxalopropionic acid (OPA), acetoacetic acid (AAA), and (alpha)-ketobutyric acid (AKBA) were determined potentiometrically, and the dissociation constant of the enolic proton of OPA, H(,2)L, was determined spectrophotometrically. The metal stability constants of AAA and AKBA were calculated for Zn(II), Al(III), and Cu(II) chelates. The stability constants of 1:1 OPA chelates of Zn(II), Al(III), and Cu(II) were determined in addition to stability constants of a deprotonated species, MH(,-1)L('-), for Zn(II) and a 2:1 complex for Al(III), ML(,2)('-). The Cu(II) investigation showed the existence of a deprotonated complex, MH(,-1)L('-), and of binuclear complexes. The kinetics of the spontaneous decarboxylation of OPA to the enolate intermediate of AKBA with subsequent ketonization, and of (beta)-deuteration via enolization, have been studied by NMR in aqueous solution at 31(DEGREES)C. Both observed and species specific rate constants have been determined for these reactions. Under the reaction conditions employed the hydrate species exists in appreciable concentrations at low pH while the concentration of the enol species is not significant. Distributions of species formed by the coordination of 2-oxalopropionic acid by Zn(II), Al(III) and Cu(II) ions are reported and kinetics of decarboxylation are discussed in terms of the species present in solution. Studies of initial rates of metal ion-catalyzed decarboxylation of 2-oxalopropionic acid show dependence on the degree of formation of the metal chelate (ML). Rate constants for the decarboxylation of ZnL, CuL, AlL('+), and AlL(,2)('-) were determined. The equilibrium constants for ML(keto) (DBLHARR) ML(enol) were evaluated for the Zn(II) and Al(III) systems as was the keto-enol equilibrium constant for AlL(,2)('-)(enol) (DBLHARR) AlL(,2)('-)(keto). The conditional Schiff base formation constants of pyridoxamine and OPA and the rates of the vitamin-B(,6) catalyzed decarboxylation of OPA were determined spectrophotometrically in basic aqueous solutions. The observed rate constant of decarboxylation exhibited pH dependence with the maximum occurring at approximately the pH corresponding to maximum ketimine formation. The pKa's and the specific rate constants of the various protonated ketimine forms have been estimated from the rate constant-pH profiles. 
650 0 |a Decarboxylation. 
650 0 |a Vitamin B6. 
650 4 |a Chemistry 
655 7 |a Academic theses  |2 lcgft 
700 1 |a Bates, George W.,  |e degree committee member. 
700 1 |a Hogg, John L.,  |e degree committee member. 
700 1 |a Martell, A. E.,  |e degree supervisor. 
710 2 |a Texas A & M University,  |e degree granting institution. 
856 4 1 |u http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=752863461&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD  |z Link to ProQuest Copy  |t 0 
856 4 1 |u https://hdl.handle.net/1969.1/DISSERTATIONS-102467  |z Link to OAKTrust copy  |t 0 
994 |a C0  |b TXA 
999 f f |s 2061a76f-df90-3c9b-b982-e1c6de996e46  |i 13891906-8e18-35bd-990d-25dae29f09d8  |t 0 
952 f f |p noncirc  |a Texas A&M University  |b J.J. Pickle Campus  |c High Density Repository  |s HDR  |d Remote Storage  |t 0  |e 1982 Dissertation K95  |h Other scheme  |i unmediated -- volume  |m A14841013750 
952 f f |a Texas A&M University  |b College Station  |c Electronic Resources  |s www_evans  |d Available Online  |t 0  |e 1982 Dissertation K95  |h Other scheme 
998 f f |a 1982 Dissertation K95  |t 0  |l Remote Storage 
998 f f |a 1982 Dissertation K95  |t 0  |l Available Online