Aminophenyl ketones

Telluroxanthone is prepared from NajTe and the diazonium salt obtained from bis(2-aminophenyl)ketone. Owing to the low yield (2%), this is not a useful preparative procedure. ... 

Another approach, the Friedlander synthesis, is to condense a 2-aminophenyl ketone with an aldehyde or ketone that contains a methylene unit (to permit enolization and subsequent aromatization), in contact with either an acid or a base as the catalyst (Scheme 3.8). 

Dialkylquinazolines 825 are available by microwave-assisted amination and ring closure of 2-acylamino phenyl-ketones 824 with ammonium formate <20070L69>. The 2-aminophenyl ketone precursors of the amides 824 are available by a photochemically induced Fries rearrangement of anilides 823, which enables a variety of different alkyl substituents to be incorporated at the 4-position of the quinazoline <20070L69>. 

Oxidation of 2-azidophenyl ketone hydrazones (455) affords the 2-azidophenyldiazoalkanes (456) which can be cyclized thermally to 1,2,3-benzotriazines (457) (75JCS(Pl)3l). Similarly, 2-aminophenyl ketone hydrazones (458) give 1,2,3-benzotriazines (457) on oxidation with lead tetraacetate (75JCS(Pl)3l). 

Sodium telluride, prepared from tellurium and sodium formaldehydesulfoxylate in aqueous sodium hydroxide, reacted with the diazonium salt that was obtained from bis[2-aminophenyl] ketone to produce... 

Patent Aminophenyl Ketones Derivatives and a Method for the Preparation... 

Aminophenyl ketones 43 reaet with triphenylphosphorane dithioeyanatc in diehloromethane solution to give the aminophosphonium salts 44 as intermediates which undergo spontaneous cyclocondensation to 4-substitiited quinazoline-2(l//)-thiones 45. ... 

From 2-Aminophenyl Ketones or 2-Aminobenzaldehydes and Urea, Carbamates, or Guanidine... 

The fusion of 2-aminophenyl ketones or 2-aminobenzaldehydes 39 with urea, guanidine, or carbamates is a useful synthetic method for the preparation of 4-substituted quinazolin-2(l//)-ones 40 and quinazolin-2-amines 46. The cyclization is usually carried out by fusing the reagents without solvent at temperatures above 150"C or in a high-boiling solvent (e.g., Decalin). The yields are generally high. 

From 2-Aminophenyl Ketones and Nitriles, Carbodiimides, or Guanidine-1-carbonitrile... 

To a 2-aminophenyl ketone 48 (1 g) was added formamide (20 mL) containing 2 drops of BFj OEtj. The mixture was heated in an oil bath at 130 -135 C for 2 h at which point TLC (25 % EtOAc in benzene) showed the disappearance of the starting material. The mixture was extracted with benzene (3 x 25 mL) and the extract dried (NajS04). The solvent was removed under reduced pressure and the solid residue crystallized (benzene/petroleum ether or acetone/petroleum ether). Liquid products were distilled. 

Amidines 9 with an appropriate ortho-carbonyl substituent, which are obtained from the respective ortho-carbonyl aniline derivatives and 0-ethyl succinimide (5-ethoxy-4,5-dihydro-3//-pyrrol-2-one), are cyclized with sodium in alcohol to quinazolin-4(3// )-ones 10a and quinazolines 10b with a 2-[(alkoxycarbonyl)ethyl] substituent at C2. The reaction can also be carried out starting from anthranilates or 2-aminophenyl ketones as a simple one-pot synthesis. ... 

Reaction of 2-aminobenzaldchyde and 2-aminophenyl ketone oximes 22 with acyl chlorides, 3+6-348 esters, acetic anhydride, or formic acid directly... 

With substrates containing a nucleophilic group sited close to a carbonyl group, on reaction with the sulfonium methylide (21) the intermediate epoxides are not isolated and instead heterocycles are generally obtained. For instance, o-aminophenyl ketones (50) react with the ylide (21) to yield the benzopyrroles (51) via the epoxides (52) (Scheme 20). 

A pyridin-2-one ring is formed by reacting a 3-aminodiazine with a reactive malonate ester such the 2,4,6-trichlorophenyl ester this cyclization needs a temperature of about 240 °C to be maintained for about 20 min [3676]. The ease of displacement of a methylthio group in compounds such as (53,8) demonstrates their usefulness a second molecule of the arylamine reacts with the methoxycar-bonyl group [3690]. An alternative method (to that described in Chapter 9, Section II.2) of synthesizing pyridazino[4,S-6]quinolin-10-ones which avoids the use of fluorophenyl ketones is oxidative cyclization of 2-aminophenyl ketones... 

Not surprisingly, C4 in 1,2,3-benzotriazines 8 is very electrophilic and easily undergoes covalent hydration across the N3-C4 bond to give, ultimately, 2-aminophenyl ketones 9.10,82 4-Phenyl-1,2,3-benzotriazine (8, R = Ph) reacted with hydrazine to form the hydrazone of 2-amino-diphenyl ketone (9, R = Ph).82 Surprisingly, the pyrido[3,2-[Pg.562]

Cinnolines are prepared by an intramolecular cyclization of o-alkenyl or o-alkynyl aryldiazonium salts. For instance, (o-aminophenyl)alkynes 6 or alkyl(o-aminophenyl)ketones 8 (via the enol form) yield 4-hydroxycinnolines 7 (the v. Richter and Borsche syntheses, respectively), o-Aminostyrenes 10 afford 3,4-disubstituted cinnolines 11 (Widman-Stoermer synthesis) ... 

An early report on this chemistry from Suzuki s group described the employment of stable Na-enolates 290 as coupling components in the synthesis of disubstituted, and even fused, indoles 292 (Scheme 9.100) [269]. The Cu(I)-mediated a-arylation of 290 with o-iodoaniline 289 initially provided a-o-aminophenyl-ketones 291, whereupon a subsequent cydocondensation reaction furnished the corresponding indole nudeus. 

Copper catalyzes the combination of e-aminophenyl ketones and methyl perfluoroalk-2-ynaoates, which produces 2-perfluoroalkylated quinolines under mild conditions (Scheme 65) (13EJ08323). While other catalysts (AUCI3, FeCl3, ZnCl2, or TiCl4) formed the quinolines, the yield... 

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