The formation of fatty acid methyl esters by transesterification with methanol can be monitored by 1H nuclear magnetic resonance spectroscopy; this accurate determination is simpler than chromatographic methods. JAOCS72, 1239-1241 (1995).

Gas‐phase basicities (GB) of strong organic bases containing the imino group were re‐examined in the light of the re‐evaluated GB values for the reference bases given in a recent compilation of Hunter and Lias. Structural (internal) effects which influence the basicity are discussed and general relations for the GB prediction are proposed for simple alkyl amidines and guanidines. These relations were used for estimation of cyclization and intramolecular H‐bonding effects. Copyright © 2000 John Wiley & Sons, Ltd.

This review is intended to give a wide scope on the uses of ion-exchange resins as catalysts or catalyst precursors in organic synthesis, for the preparation of fine or intermediate chemicals. Twelve families of reaction have been covered and presented according to the molecules to be synthesized, regardless of the anionic or cationic nature of the resins; thus, ∼300 references have been selected from January 1980. In acid-catalyzed reactions, the contribution of both Lewis acidity and Bro ¨nsted acidity are mentioned, and, when available, some aspects related to the stability or the recycling of the catalysts are reported. In base-catalyzed reactions, the importance of the thermal stability of anionic resins has been underlined. A table that is included as an appendix provides some data on the resins quoted here.