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Potassium tert-butoxide is used as a strong non-nucleophilic base in organic chemistry. It plays an active role in dehydrohalogenation reactions. It is also useful for greener amidation of esters. It serves as an intermediate in Mizoroki-Heck-type reactions. Furthermore, it is used as an initiator in anionic polymerization of carbazolyl-substituted oxiranes. It catalyzes the reaction of hydrosilanes and heterocyclic compounds to give the silyl derivatives with evolution of hydrogen.
Strong base of relatively low nucleophilicity. Review: Chem. Rev., 74, 45 (1974). The nucleophilicity is increased in the presence of 18-crown-6; the basic strength less so: J. Org. Chem., 43, 447 (1978).
For generation of dibromocarbene, see Bromoform, A11904. In combination with a solid-liquid phase-transfer catalyst in the absence of solvent, has been recommended for the dehydrobromination of alkyl bromides to alkenes: J. Org. Chem., 49, 1138 (1984): with 18-crown-6, is effective for the dehydrobromination of vic-dibromides: Liebigs Ann. Chem., 1 (1980), and in the dehydrochlorination of gem-dichloroalkanes to give alkynes: J. Org. Chem., 39, 3285 (1974).
Deprotonation of an ɑ-halo sulfone, followed by Ramberg-Backlund reaction with extrusion of SO2, gives an alkene: J. Am. Chem. Soc., 110, 4866 (1988); Org. React., 25, 1 (1977); Org. Synth. Coll., 8, 212 (1993):
For cyclization-elimination of ɑɑ-dibromoneopentyl ketone to di-tert-butylcyclopropenone, a precursor of tri-tert-butylcyclopropenium tetrafluoroborate, see: Org. Synth. Coll., 6, 991 (1988); for reaction scheme, see Neopentyl chloride, L02365.
For intramolecular cyclization of a dinitrile to an unsaturated vic-amino nitrile (Thorpe-Ziegler reaction), see: Org. Synth. Coll., 6, 932 (1988).
Treatment of a methyl ester in ether with the reagent provides a simple method for preparation of tert-butyl esters: Synlett, 658 (2001).
Combinations of KO-t-Bu with other strong bases are used to generate "superbasic" media, e.g. with n-BuLi: J. Organomet. Chem., 8, 9 (1967); Pure Appl. Chem., 60, 1627 (1988); Tetrahedron Lett., 29, 4991 (1988); see also Phenylacetylene, A12139, 2-Methylindole, A10764, etc. In combination with Li 3-aminopropanamide, promotes the "zip" reaction for isomerizing alkynes to the terminal position; see 1,3-Diaminopropane, A11932, and Org. Synth. Coll., 8, 146 (1993). For use in combination with LDA for isomerization of epoxides to allylic alcohols, see Cyclohexene oxide, A13185.
Suzuki, C.; Kato, K.; Tsuji, A. B.; Zhang, M. R.; Arano, Y.; Saga, T. Inhibition of radical reactions for an improved potassium tert-butoxide-promoted 11C-methylation strategy for the synthesis of alfa-11C-methyl amino acids. J. Labelled Compd. Radiopharm. 2015, 58 (3), 127-132.
Midya, G. C.; Kapat, A.; Maiti, S.; Dash, J. Transition-Metal-Free Hydration of Nitriles Using Potassium tert-Butoxide under Anhydrous Conditions. J. Org. Chem. 2015, 80 (8), 4148-4151.
Dichiarazioni di rischio (UE): H228-H251-H314-H318
Flammable solid. Self-heating: may catch fire. Causes severe skin burns and eye damage. Causes serious eye damage.
Dichiarazioni precauzionali: P210-P260u-P303+P361+P353-P305+P351+P338-P405-P501a
Keep away from heat/sparks/open flames/hot surfaces. - No smoking. IF ON SKIN (or hair): Remove/Take off immediately all contaminated clothing. Rinse skin with water/shower. IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing. Store locked up. Dispose of contents/container in accordance with local/regional/national/international regulations.