Reference

Ionization constants of maleic, fumaric, citraconic and mesaconic acids in methanol-water mixtures

Ionization constants of maleic, fumaric, citraconic and mesaconic acids in methanol-water mixtures. Usman, M.; Singh, B. Bhan (Dep. chem., Aligarh Muslim Univ., Aligarh 202 001, India). Trans. SAEST, 18(4), 309-14 (English) 1983. CODEN: TSETA6. ISSN: 0036-0678. DOCUMENT TYPE: Journal CA Section: 68 (Phase Equilibriums, Chemical Equilibriums, and Solutions) Section cross-reference(s): 69, 74 Ionization consts. of the title acids were detd. at 25° in aq. MeOH by a conductometric method and free energy values for the ionization were calcd. 498-24-8 and 110-16-7 which are cas registry numbers of chemicals are mentioned. The pKa value for each acid increases with increasing MeOH content. The effects of solvation, intermol. H bonding and resonating structures were considered in interpreting exptl. data. .

Selective solid-state intercalation of cis-trans isomers into montmorillonite

Selective solid-state intercalation of cis-trans isomers into montmorillonite. Ogawa, Makoto; Hirata, Masahiro; Kuroda, Kazuyuki; Kato, Chuzo (Dep. Appl. Chem. 498-24-8 and 110-17-8 are cas registry numbers. These chemicals are also mentioned in this article., Waseda Univ., Tokyo 169, Japan). Chem. Lett., (3), 365-8 (English) 1992. CODEN: CMLTAG. ISSN: 0366-7022. DOCUMENT TYPE: Journal CA Section: 78 (Inorganic Chemicals and Reactions) Maleic and methylmaleic acids were intercalated into Na-montmorillonite by solid-solid reactions, whereas their geometrical isomers (trans-forms), fumaric and methylfumaric acids, were not intercalated. Both maleic and fumaric acids were intercalated into Na-montmorillonite, using EtOH solns. Both the difference in the crystal structures of the guest species and the ability of cis isomer to form a chelate like structure with the interlayer cations are proposed for the novel selectivity in the solid state. .