Ethynyl phenyl ketone

Ethynyl phenyl ketone HCsCCOPh, is prepared as follows ... 

Fischer14 15 prepared the unsubstituted pyrido[l,2- /]pyrimidinium salt (16) and its 4-phenyl derivative (9 R1 = Ph) by reacting 2-aminopyridinium perchlorate with propargylaldehyde and with ethynyl phenyl ketone, respectively. 

Phenyl 2-(trimethylsilyl)ethynyl sulfone (118) can act as a vinyl cation synthon (equations 93 and 94)78 79. Thus, the reaction of enolates with 118 and subsequent desulfonylation of the adduct gives a-vinyl ketone, such as 119 and 120. 

The aryl vinyl tellurium compounds formed in these reactions (p. 401) are obtained exclusively, or at least predominantly, as the (Z)-isomers. With ethynyl ketones, aldehydes, acids, and esters, the nucleophile attacks the ethync carbon in the -position to the carbonyl group10, ". Benzenetellurolate and bis[phenylethynyl] ketone produced only bis[2-phenyl-2-phenyltelluroethynyl] ketone and no monoadduct11. 

In Table 1, the moisture uptake of cured and uncured Navy P3-2300-PE resin after 24 hours of immersion is compared to a number of other high-temperature polymer resins. The moisture uptake of the Navy P3 oligomer is nearly identical to that of the commercial P3 thermoplastic. Other commercial thermoplastics, such as poly(ether ether ketone), with very similar chemical compositions, exhibit similarly low levels of moisture uptake. On the other hand, the Navy P3 resins absorbs about 85% less water than the commercial polyimide Kapton HN. Since thermosetting phenyl ethynyl end-capped polyimides have moisture uptake characteristics that are similar to Kapton HN, with around 3% weight gain on exposure to 95% relative humidity (77), void-free composites based on Navy P3 resins should exhibit greatly reduced moisture uptake compared to those based on thermosetting polyimides. 

Phenyl ethynyl ketone (2). To a stirred solution of phenyl elhynyl earbinol 1 (342 g. 2 59 moll. In MejCO (500 mL) was added slowly a solution of C1O3 (175 g, 1.75 mol), hi water (500 niL) and 98% H2SO4 (158 mL) under N2 at +5 C In 4-5 h. After stimng for a further 30 min, the mocture was diluted with water and the product extracted with Et20. Evaporation of the solvent and recrystaltization of the residue from MeOH H2O afforded 258 g of 2 (68%), np 50-51°C... 

Similarly, the 2-azidoethylene-l,l-dicarbonitriles (92) were found to react with aniline to give the corresponding anilino derivatives 121 Reaction of phenyl ethynyl ketone with sodium azide in an aqueous medium, it will be recalled, gave the isoxazole 74 (R = H). When this reaction was carried out in dimethylformamide, quite different results were found in this case the sodium salt of 4-benzoyl-1,2,3-triazole was isolated in good yield . The formation of this product... 

Acyl- and 3-aroyl-meso-benzanthrones can readily be obtained by a Diels-Alder reaction of methyleneanthrone and a,/ -ethynyl ketones, with yields of 50-70%, the addition being accompanied by oxidation.— E A soln. of methyleneanthrone and phenyl ethynyl ketone in acetic acid refluxed 3/4 hr. 3-benzoyl-meso-benzanthrone. (F. Irving and A. W. Johnson, Soc. 1948, 2037.)... 

Danishefsky and coworkers have used the racemic P-phenylsulfinyl-a,P-unsaturated ketone (160) as an a,P-ethynyl carbonyl synthetic equivalent and found that the phenylsulflnyl group did not compete with the carbonyl group in determining the regioselectivity of cycloaddition with the l-methoxy-3-trimethylsilyloxy-1,3-butadiene (161), now known as Danishefsky s diene [140] (Scheme 5.54). Loss of methanol and phenyl sulfenic acid from the initial cycloadduct (162) gave the aromatic product (163). 

For instance, photolysis of aryl esters of phenylpropiolic acid (21) gives rise to o-hydroxyaryl phenyl-ethynyl ketones (22). The latter compounds can undergo cyclization in two different ways, depending upon the reaction conditions When potassium carbonate in acetone is used, flavones (23) are formed by a 6-endo-dig process by contrast, the use of sodium ethoxide in ethanol favors the 5-exo-dig process,to give aurones (24) as the major products (Scheme 6). The side-chain functionality can be masked, as in the case of the protected ketoesters (25), whose irradiation and subsequent deprotection provide an alternative entry to the flavone system (Scheme 6). ... 

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