Tert-BuOK

Intermolecvlax energy transfer is apparently involved in the anomalous chemiluminescence of phthalic hydrazide in aprotic solvent (DMSO/tert.BuOK/Og) 124) the energy of excited phthalated ianion is transferred to phthal-hydrazide monoanion which then emits at 525 nm with relatively low quantum yield. This phenomenon has not been observed in aqueous systems 2>. 

The structure of anhydrovobasindiol (35, C20H24N20, MP 208°C, [a]D —243°) was based almost entirely on chemical evidence. Hydrogenation of 35 gave a dihydro derivative (C20H26N20, MP 191-193°C), which formed a meth-iodide on reaction with Mel. Hofmann elimination with tert-BuOK in tert-BuOH... 

Kunitomo et al. reported that air oxidation of dehydroaporphines, including 2,10-dimethoxydehydroaporphine (84a), dehydronuciferine (85a), and dehydro-nantenine (86a), with tert-BuOK in DMSO gave corresponding A-meth-... 

Reaction of the ketosulfone (ix) with 2-chloro-1,3-bis(dimethylamino)trimethinium salt (xix) in the presence of an equimolar amount of tert-BuOK followed by treatment with acetic acid and TFA and reflux with an excess of ammonium hydroxide. 2-Chloro-1,3-bis(dimethylamino)trimethinium hexafluoro-phosphat (xix) is obtained by reaction of chloroacetic acid with hot dimethylformamide and POCI3. Finally the reaction mixture is treated with NaOH and hexafluorophosphoric acid in water. 

In homogeneous systems the tight ion pair 12 is formed, the collapse of which depends on the electronic effects and the steric interactions of the substituents. The stability of this ion pair determines the intramolecularity of the rearrangement.121 For example, when (+)-3-phenyl-l-butene was isomerized in tert-BuOK-tert-BuOD, the recovered starting material was deuterium-free and exhibited the same rotation as the starting material, and the product m-2-phenyl-2-butene contained 0.46 deuterium at C(4). This indicates that the isomerization is at least 54% intramolecular.126 Proton migration in perdeutero-l-pentene in ferf-BuOK-DMSO was demonstrated to proceed almost exclusively in an intramolecular manner.127... 

Methyl-substituted aromatics may also be converted to the corresponding carboxylic acids. As was mentioned above, a shift in the selectivity of the autoxidation of methyl-substituted arenes is brought about by metal ions eventually producing carboxylic acids. Carboxylic acids may also be formed by the base-catalyzed autoxidation of methyl-substituted arenes.848 Oxidation with tert-BuOK in HMPA affords carboxylic acids in moderate yields with very high selectivities. 

Styrenes dimerize and cyclodimerize depending on the catalyst, the reaction conditions, and the substrate. a-Methylstyrene gives cyclic dimer 9 in 93% yield (tert-BuOK, 160°C), whereas linear dimers (isomeric 2,5-dipehylhexenes) are formed in 83% yield at higher temperature (225°C).35 In contrast, a very low yield (11%) of cyclic dimer 10 was attained in the reaction of styrene ... 

To a mixture of 50 g 2-[4-[(4-chlorophenyl)phenylmethyl]-l-piperazinyl]-ethanol and 225 ml of tert-butanol at 45°C under a nitrogen was added 21 g tert-BuOK. The temperature was raised to 75-80°C and the mixture was kept at this temperature. After 45 min was added 11 g sodium chloracetate after 1.5 hour was added 5.2 g tert-BuOK after 2 hours was added 5.64 g sodium chloracetate after 2.5 hours was added 1.9 g tert-BuOK after 3 hours was added 1.9 g sodium chloracetate after 3.5 hours was added 0.8 g tert-BuOK and after 4 hours was added 1.13 g sodium chloracetate. Then about 150 ml tert-butanol was distilled of, 190 ml of water was added and the distillation of tert-butanol was continued until the temperature of the vapour reaches 100°C. To the reaction mixture was added 60 ml of water and 8 ml concentrated hydrochloric acid to pH 8. Unreacted 2-[4-[(4-chlorophenyl) phenylmethyl]-l-piperazinyl]-ethanol was extracted with diethyl ether. The aqueous phase was acidified to pH 5 by addition of hydrochloric acid and extracted with dichloromethane (200 ml x 3). The extract was dried over MgS04, filtered and concentrated in a rotary evaporator. An obtained oil was allowed to crystallize by addition of 150 ml of 2-butanone, yields of 2-[4-[(4-chlorophenyl)phenylmethyl]-l-piperazinyl]-ethoxy]acetic acid 55.5%, M.P. 146-148°C. 

From 4-bromomethylbenzonitrile and lhl-[l,2,4]triazole was obtained 4-[l,2,4]triazol-l-ylmethylbenzonitrile. Treatment of that with strong base (tert-BuOK) results in formation of the anion by removal of the relatively acidic benzyl proton. This anion was condensed with p-fluorobenzinitrile to give benzhydryl tetrazole (Letrozole). 

The hydroxy group of 7-hydroxy-l,3,4,6,7,116-hexahydro[l,4]ox-azino[3,4-a]isoquinoline was acylated with tosyl chloride, and the tosyloxy group was eliminated by the treatment with tert-BuOK to give 1,3,4, 116-tetrahydro-[l,4]oxazino[3,4-a]isoquinoline (67BRP1094470, 67NEP 6611733). 

Oxopyrido[l,2,3-de]-l,4-benzoxazine-6-carboxylates (194, X = O) could be prepared from l-(2-hydroxyethyl)-4-oxo-l,4-dihydroquinoline-3-carboxylates (195) by treatment with a base (NaH, KOH, KF, K2C03 or tert- BuOK) [86CPB4098 87GEP3522406, 87JAP(K)87/198685,... 

Chemical Modification. Reactions on the macromolecular polyenes were carried out by procedures described previously (3, 4). PhHgCBr3 is obtained by a modification of Seyferth s method (21) from PhHgBr and HCBr3 in presence of a base. Yields similar to those reported in the literature are obtained more easily by replacing the complex (tert-BuOK— tert-BuOH) with a solution of sodium tert-amylate in benzene as prepared by Conia (24). This reagent was, in fact, used systematically in place of potassium tertf-butylate it is easier to use and can be prepared completely free of alcohol. 

At the residue level, all the chlordan compounds listed in Table II can be simultaneously confirmed using a tert-BuOK/tert-BuOH reagent. Silylation or acetylation of the hydroxy products do not affect any accom-... 

Sodium enolates of diethyl 2-oxoalkylphosphonates react with diethyl chlorophosphate to produce enol phosphates. Low-temperature treatment of enol phosphates with tert-BuOK induces the ()-elimination of potassium diethyl phosphate and formation of diethyl 1-alkynylphosphonates in good yields (43-95%, Scheme 7.113). However, the reaction is prone to prototropic isomerization and diethyl 2-oxobutyIphosphonate leads to a mixture of diethyl 1-butynyIphosphonate (43%) and diethyl 2-butynylphosphonate (51%). ... 

C) B, tert-BuOK, dioxane (solvent) -> C (94%, HALLER-BAUER-type cleavage). What are the structures of the products A - C and their modes of formation ... 

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