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Allyl esters can be obtained by a Finkelstein-rearrangement–elimination reaction of 2-chloro-1-(chloromethyl)ethyl esters induced by NaI. Sodium iodide can be used below equivalence using a reductive agent as sodium thiosulfate. High yields are obtained with most of the diverse esters studied. The method described avoids the use of allyl alcohol as a reagent. 2-Chloro-1-(chloromethyl)ethyl esters are prepared from glycerol, the main by-product of biodiesel industry. The effectiveness of iodine as reagent to hydrolyze allyl esters is also confirmed. This work was supported in part by a Grant-in-Aid for the Secretaría de Estado de Política Científica y Tecnológica of the Spanish Ministry of Education and Culture (Contract grant number: CTQ2006-07451/PPQ). The authors are grateful to the Comissionat per a Universitats i Recerca del Departament d'Innovació, Universitats i Empresa de la Generalitat de Catalunya and to the European Social Fund (ESF) for the FI grant of Marc Escribà Gelonch.

We describe here the first example in which glycerol has been transformed into chlorohydrin esters using an ionic liquid and hydrated aluminium chloride. The method avoids using Crown-18 ether, which was needed to obtain a similar yield when KCl was used. Alkyl and aryl acids can be used, although yields are very dependent on the carboxylic acid used.

The use of iodine as a catalyst and either acetic or trifluoroacetic acid as a derivatizing reagent for determining the enantiomeric composition of acyclic and cyclic aliphatic chiral alcohols was investigated. Optimal conditions were selected according to the molar ratio of alcohol to acid, the reaction time, and the reaction temperature. Afterwards, chiral stability of chiral carbons was studied. Although no isomerization was observed when acetic acid was used, partial isomerization was detected with the trifluoroacetic acid. A series of chiral alcohols of a widely varying structural type were then derivatized with acetic acid using the optimal conditions. The resolution of the enantiomeric esters and the free chiral alcohols was measured using a capillary gas chromatograph equipped with a CP Chirasil-DEX CB column. The best resolutions were obtained with 2-pentyl acetates (α = 3.00) and 2-hexyl acetates (α = 1.95). This method provides a very simple and efficient experimental workup procedure for analyzing chiral alcohols by chiral-phase GC. The authors are grateful to the Secretaría de Estado de Política Científica y Tecnológica of the Spanish Ministerio de Ciencia y Tecnología (CTQ2009-14699-C02-01) and Departament d’Universitats, Recerca i Societat de la Informació of the Generalitat de Catalunya (2001SGR00309) for financial support. M. Oromi-Farrús thanks the Ministerio de Educación y Cultura for the Predoctoral Fellowship no. AP 2001–3761.

Iodine values (IVs) of some biodiesel samples were analyzed using both 1H NMR and a standard iodometric method. 1H NMR was carried out with and without 1,4-dioxane as an internal standard (IS). The results obtained using 1H NMR with 1,4-dioxane as an internal standard showed better linear fitting and correlation with the iodometric method than NMR without the IS. The proposed 1H NMR_IS method allows determination of the IV using smaller samples than the iodometric method. Moreover, the determination can be carried out in less than 15 min, dramatically less than the time needed to carry out the iodometric method. Authors are grateful to the Ministerio de Medio Ambiente (Project Ref.: A323/2007/3-02.5) for the financial support. The authors are also grateful to Mr. Rafael Prims from Raluy S.L. for the biodiesel supply and to Albert Tomàs and Montserra Llovera for the IV determination by the iodometric method and for the acidic profile analyses

Haloesterification of diverse diols with various carboxylic acids was achieved using potassium halides (KX) as the only halide source in ionic liquids. The best yield was obtained in [BMIM][PF6] when 1,2-octanediol, palmitic acid and KBr were used. This yield was 85% and the regioisomer with the bromine in primary position was present in a 75:25 ratio. The regioisomeric ratio could be improved using either KCl or some phenylcarboxylic acids. [BMIM][PF6] acts as both reaction media and catalyst of the reaction. To the best of our knowledge, this type of combined reaction using an ionic liquid is unprecedented. The other solvents tested did not lead either to the same yield or to the same regioisomeric ratio.

Preparation of (S)-1-chloro-2-octanol and (S)-1-bromo-2-octanol was carried out by the enzymatic hydrolysis of halohydrin palmitates using biocatalysts. Halohydrin palmitates were prepared by various methods from palmitic acid and 1,2-octanediol. A tandem hydrolysis was carried out using lipases from Candida antarctica (Novozym® 435), Rhizomucor miehei (Lipozyme IM), and “resting cells” from a Rhizopus oryzae strain that was not mycotoxigenic. The influence of the enzyme and the reaction medium on the selective hydrolysis of isomeric mixtures of halohydrin esters is described. Novozym® 435 allowed preparation of (S)-1-chloro-2-octanol and (S)-1-bromo-2-octanol after 1–3 h ofreaction at 40 °C in [BMIM][PF6].