Benzophenone potassium

Metal ketyls are ion-radicals analogous to semiquinone ion radicals and may be considered either oxygen or carbon free radicals. They are readily prepared by treating aromatic ketones with alkali metals in dry ether, benzene, or liquid ammonia under an inert atmosphere.124 125 Benzophenone potassium has been shown to be paramagnetic in the solid state.126... 

Oxidation of the quinine C-9 hydroxy substituent to the ketone is best accomplished using the Woodward3 benzophenone/potassium t-butoxide method, now using toluene. The other oxidation methods investigated (Swern, Jones, ROCI variations) were less effective or limited because of the poor solubility of the substrate. Thermodynamic equilibration of these ketones has also been reported.3... 

U.S. Patent 2,409,754 (1946) to H. R. Henze, Parke-Davis and Co. involves reacting benzophenone, potassium cyanide and ammonium carbonate in 60% ethanol. It can also be prepared by reacting benzophenone, sodium cyanide and ammonium bicarbonate according to Scheme 1. 

Dissolving metals initially convert aldehydes, ketones, and esters into radical anions. Subsequently, proton donors may react with the latter, which leads to neutral radicals. This mode of reaction is used, for example, in the drying of THF or ether with potassium in the presence of the indicator benzophenone. Potassium and benzophenone react to give the deep-blue potassium ketyl radical anion A (Figure 14.45). Water then protonates ketyl A to the hydroxylated radical B as long as traces of water remain. Further potassium reduces B via another electron transfer to the hydroxysubstituted organopotassium compound C. C immediately tautomerizes to the potassium alkox-ide D. Once all the water has been consumed, no newly formed ketyl A can be pro-tonated so that its blue color indicates that drying is complete. 

Related Reagents. w-Butyllithium-potassium f-butoxide Potassium Amide Potassium Hexamethyldisilazide Potassium f-butoxide-benzophenone Potassium f-butoxide-r-butyl Alcohol Complex /t-butyllithium-Potassium it t-butoxide Potassium t-butoxide-18-crown-6 Potassium r-butoxide-dimethyl Sulfoxide Potassium f-butoxide-hexamethylphosphoric Triamide Potassium Diisopropylamide Potassium f-heptoxide Potassium Hydroxide Potassium 2-methyl-2-butoxide. 

In a water-free medium chain growth polymerization can be initiated by numerous metal-organic or basic compounds, such as trityl sodium [81], butyl lithium [80,81], naphthyl sodium [80,81], benzophenone potassium [81], sodium methoxide [80,81], lithium organocuprates [85] and rhodium(I) complexes [86] or ammonia [87], er -phosphines [80,88], aliphatic amines [89], cyclic amines [90], and aromatic amines (pyridine [91,92],... 

The condensation of aldehydes and ketones with succinic esters in the presence of sodium ethoxide is known as the Stobbe condensation. The reaction with sodium ethoxide is comparatively slow and a httlo reduction of the ketonic compound to the carbinol usually occurs a shorter reaction time and a better yield is generally obtained with the more powerful condensing agent potassium ieri.-butoxide or with sodium hydride. Thus benzophenone condenses with diethyl succinate in the presence of potassium [Pg.919]

Quininone (2). Potassium melal (10 g, 0 2S at g) was dissolved In t-BuOH (200 mL). The excess o< t-BuOH was removed in vacuum until a dry mobile powder was obtained. A suspension oi t-BuOK and qumlne 1 (32.4 g, O.t mol), benzophenone (91.0 g, 0 5 moQ in PhH (500 mL) was refluxed for 15-18 h under Ng The cooled mixture was poured into ice and extracted with 10% HCI until the HCI was coiortess. The aad extract was washed with EIzO and dripped with stirring into NH4OH and ice Extraction with EI2O, washing of the extract with brme and evaporation of the extract afforded a total of 30-32 g of 2 (95-98%), mp 106-108 C. 

Dry benzene was obtained by doubly distilling high purity benzene from a soln containing the blue ketyl formed by the reaction of sodium-potassium alloy with a small amount of benzophenone. 

Oxidation of Pluviine (276), isolated from Narcissus pseudonarcissus. Narcissus incomparabilis, and Lycoris radiata Herb., with benzophenone and potassium rerr-butylate yielded a red phenol-betaine 277 from which one neutral covalent form can be drawn (Scheme 90). The betaine has absorption maxima Imax (loge) in a buffer at pH 10 at 240 (4.49), 325 (4.46), 360 (3.58), 380 (3.27), and 490 (3.26) nm. In dilute HCl, a salt is formed [lmax = 260 (4.57), 295 (4.39), 340 (3.76), 355 (3.84), 400 (3.62) nm] (57CB363). The oxidation of the alkaloid Caranine gives a similar betaine, the 1,3-dioxolo derivative 278 (56CIL348). 

Fluproquazone (97) contains a 2-quinazolinone nucleus and is found to be an analgetic agent useful in mild to moderate pain. One of the preparations involves reaetion of 2-isopropylamino-4-methyl-4 -fluoro-benzophenone (96) with potassium cyanate in hot acetic acid [27],... 

Chloro-1 -methyl-6-phenyl4H-s-triazolo-[4,3-a] [1,4] -benzodiazepine A stirred suspension of 5-chloro-2-[3-(bromomethyl)-5-methyl4H-1,2,4-triazol4-yl] -benzophenone (391 mg, 0.001 mol) in tetrahydrofuran (15 ml) was cooled in an ice-bat hand treated with a saturated solution of ammonia in methanol (12.5 ml). The resulting solution was allowed to warm to ambient temperature and stand for 24 hours. It was then concentrated in vacuo. The residue was suspended in water, treated with a little sodium bicarbonate and extracted with methylene chloride. The extract was washed with brine, dried with anhydrous potassium carbonate and concentrated. The residue was crystallized from methylene chloride-ethyl acetate to give... 

Benzohydrol has been obtained by reducing benzophenone with sodium amalgam,1 with metallic calcium and alcohol,2 with hydrogen in the presence of a catalyst,3 with zinc, aluminium or sodium in strongly alkaline solutions,4 with zinc dust and alcoholic potassium hydroxide solution,5 and electrolytically.6... 

Fujiwara, M., Fukui, M. and Tanimoto, Y. (1999) Magnetic orientation of benzophenone crystals in fields up to 80.0 kOe./. Phys. Chem. B, 102,2627-2630. Fujiwara, M., Tokunaga, R. and Tanimoto, Y. (1998) Crystal growth of potassium nitrate in a magnetic field of 80kOe./. Phys. Chem. B, 102, 5996-5998. 

Another photocyclization to a benzo[c]phenanthridine was reported (127). Oppenauer oxidation of ( )-ophiocarpine (92) with potassium fm-butoxide and benzophenone in dioxane effected C-6—N bond cleavage to afford the hydroxyisoquinoline 219 via berberinephenolbetaine (121) (Scheme 39). Although photolysis of 219 gave only the oxepine 221, that of its methyl ether 220 furnished directly norchelerythrine (222) through electrocyclization followed by spontaneous elimination of methanol. 

Benzophenoneoxime has been prepared in quantity by treating an aqueous alcoholic mixture of benzophenone and hydroxyl-amine hydrochloride with hydrochloric acid,2 with sodium carbonate,3 with alcoholic potassium hydroxide,4 or with aqueous sodium hydroxide. It has also been obtained by treating bis-nitrosylbenzohydryl with alcoholic potassium hydroxide,6 and by the oxidation of a-aminodiphenylmethane with magnesium persulfate solution.7... 

Diphenylmethane reacts with dioxygen in the presence of potassium 1,1-dimethylethoxide in various solvents (dimethylformamide [DMF], hexamethylphosphoramide [HMPA], pyridine) to produce nearly 100% yields of benzophenone [284]. The adduct of benzophenone with dimethylsulfoxide (DMSO) [l,l-diphenyl-2-(methylsulfinyl)ethanol] is formed as the final product of the reaction. The stoichiometry of the reaction and the initial rate depends on the solvent (conditions 300 K, [Ph2CH2] = 0.1mol L [Me3COK] = 0.2mol L 1,p02 = 97kPa). 

Hexafluoroisopropylidene-unit-containing aromatic poly(ether ketone)s were first synthesized from an alkaline metal salt of Bisphenol AF (1) and 4,4 -difluoro-benzophenone.14 Cassidy and co-workers prepared hexafluoroisopropylidene-unit-containing poly(ether ketone)s by condensing 2,2-bis[4-(4-fluorobenzoyl)-phenyl]-l,l,l,3,3,3-hexafluoropropane (9) and 2,2-bis[4-(4-fluorobenzoyl)-phenyljpropane (10) with Bisphenol AF (1) or Bisphenol A (4) (Scheme 7).15 The reactions are nucleophilic aromatic displacements and were conducted in DMAc at 155- 160°C with an excess of anhydrous potassium carbonate. After 3 to 6 h of reaction, high-molecular-weight poly(ketone)s are obtained in high yields. 

Thus by adding about 2.0 g of benzophenone hydrozone to a mixing of 2.0 g of a mixing of sublimed potassium t.butoxide in 5 ml of DMSO, with constant stirring the reaction was complete in 8 hrs. 

To a solution of 4 g. of benzophenone in 25 c.c. of alcohol, cooled solutions of 3 g. of hydroxylamine hydrochloride in 6 c.c. of water and 5 g. of potassium hydroxide in 5 c.c. of water are added and the whole is heated under reflux on the water bath for two hours. The product is then poured into 50 c.c. of water, any unchanged ketone is removed by filtration after shaking to cause aggregation, the filtrate is faintly acidified with dilute sulphuric acid, and the free oxime recrystallised from alcohol. Melting point 140°. 

THF was freshly distilled under argon over potassium or sodium/benzophenone. 

Tetrahydrofuran was purchased from Wako Pure Chemical Industries, Ltd., Osaka, Japan (also available from Fisher Scientific Co.) and distilled from potassium benzophenone ketyl before use. 

The convergent synthesis of a range of aryl ester dendrimers with peripheral tetrathiafulvalene units was also reported (Devonport et al. 1998). The dendrimers acquire some amount of the cation-radical tetrathiafulvalene tips on reacting with iodine in solutions. Another promising material is polyphenylene dendrimers functionalized with benzophenone units. On being transformed into the potassium ketyl derivatives, the dendrimers bring forth intermolecular biradicals. These technically attractive species contain four-membered cycles that coordinatively combine two potassium cations... 

As logical as this diagnostic method is, one needs to realize its lack of absolute applicability. The observed magnitude of the kinetic isotopic effect is not great, and the aforementioned statement of independence of the electron affinity from the increase in molecular mass of the substrate is not obvious. This postulate should be proved in each case. Benzophenone, taken as an isotopic mixture of C=0 and C=0 gives a mixture of anion-radicals with a decreased proportion of C=0 isotomer when reduced with potassium in HMPA (Stevenson et al. 1987b). In effect, this means that for the heavier isotopomer of benzophenone, the electron affinity is smaller. 

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