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Phase transfer catalyst Tetra-n-butylammonium bromide is used as a phase transfer catalyst for the preparation of lactones by cyclization of potassium salt of µ-bromocarboxylic acids and beta-lactones from beta-bromoacid by cyclization. It is also involved in the Curtius rearrangement, N-alkylation of aromatic carboxamides. It plays an important role as an ionic liquid in the regioselective O-alkylation reactions. It is also used in the preparation of polymer solar cells and single component green-light emitting electrochemical cells.
Phase-transfer catalyst of wide application. Some illustrative examples are given below. See also Appendix 2.
K salts of ω-bromocarboxylic acids can be cyclized to lactones under effectively "high-dilution" conditions by extracting into toluene in the presence of a small amount of catalyst. The 16-membered ring lactone was formed in 92% yield: J. Org. Chem., 48, 1533 (1983).
Primary alkyl chlorides can be converted to alcohols in excellent yield by phase-transfer reaction with sodium formate and hydrolysis of the resulting formate esters: Synthesis, 763 (1986).
ß-Lactones are formed by the cyclization of ß-bromoacids under phase-transfer conditions: Chem. Pharm. Bull., 29, 1063 (1981).
An improved procedure for the Curtius rearrangement involves reaction of acid chlorides with azide ion under phase-transfer conditions: Synthesis, 38 (1983).
Aromatic carboxamides undergo N-alkylation with alkyl halides using KOH under solvent-free conditions: Synth. Commun., 22, 1661 (1992).
Has been used as an "ionic liquid" in the regioselective O-alkylation of ambident nucleophiles: Tetrahedron Lett., 33, 4435 (1992). A method is described whereby the "solvent" can be recovered quantitatively. A semi-molten mixture with KF or CsF has been found to be an effective system for fluorodehalogenation of, e.g., benzyl bromide: J. Fluorine Chem., 73, 185 (1995).
Effective catalyst for amination reactions of alkyl or activated aryl halides, by increasing the solubility of ammonia in organic media: J. Chem. Soc., Chem. Commun., 267 (1987).
Tzirakis, F.; Stringari, P.; Von Solms, N.; Coquelet, C.; Kontogeorgis, G. Hydrate equilibrium data for the CO2+ N2 system with the use of Tetra-n-butylammonium bromide (TBAB), cyclopentane (CP) and their mixture. Fluid Phase Equilib. 2015, 408, 240-247.
Akiba, H.; Ueno, H.; Ohmura, R. Crystal Growth of Ionic Semiclathrate Hydrate Formed at the Interface between CO2 Gas and Tetra-n-butylammonium Bromide Aqueous Solution. Cryst. Growth Des. 2015, 15 (8), 3963-3968.
Dichiarazioni di rischio (UE): H315-H319-H335
Causes skin irritation. Causes serious eye irritation. May cause respiratory irritation.
Dichiarazioni precauzionali: P261-P280a-P305+P351+P338-P304+P340-P405-P501a
Avoid breathing dust/fume/gas/mist/vapours/spray. Wear protective gloves and eye/face protection. IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing. IF INHALED: Remove to fresh air and keep at rest in a position comfortable for breathing. Store locked up. Dispose of contents/container in accordance with local/regional/national/international regulations.