Diphenyl Ketone Derivatives

B A sesquihydrate was obtained by crystallisation of the ketone in water [5928], The melting point is determined after water elimination (100°/0.04 nun/1 h). 

Martin, Aromatic Hydroxyketones Preparation and Physical Properties, 1627 

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The kinked dicarboxy compounds obviously has considerable capability for decreasing the melt transitions with increasing substitution for the terephthalic acid. A decrease to below 300°C is already achieved with the diphenyl ether derivatives-(3,4 -0 and 4,4 -0) at a degree of substitution corresponding to 30%. For the corresponding diphenyl ketone derivatives (3,4 -K and 4,4 -K) a somewhat higher degree of substitution is required, 35-40%, to get a comparable melt depression. The more stiff structure of the ketones compared to the ethers may be connected with this kind of behaviour. However, further increase in the amounts has a very drastic effect on the melt transition. 

Acyl Groups Located on Different Rings 21.2.1 Diphenyl Ketone Derivatives... 

Acyl Groups Located on Different Rings [5958] p. 1636 21.2.1 Diphenyl Ketone Derivatives [5958] p. 1636... 

The thermolysis of 4-azidophenyl methyl ketone in morpholine at 170°C yields a mixture of the expected 5-acetyl-2-morpholino-3f/-azepine (33) and 6-acetyl-2-morpholino-3//-azepine (34), the product of a unique and totally unexpected thermal rearrangement of the 5-acetyl derivative.119 Similar results can be obtained in hot piperidine, whereas thermolysis of 4-azido-diphenyl ketone under similar conditions yields only the 6-benzoyl-2-(cycloalkylamino)-3//-azepines (7-18%) accompanied by much tar. 

To examine the viability of CIM a number of photoreactions (electrocyclic reactions, Zimmerman (di-n) reaction, oxa-di-7i-methane rearrangement, Yang cyclization, geometric isomerization of 1,2-diphenyl-cyclopropane derivatives, and Schenk-ene reaction) which yield racemic products even in presence of chiral inductors in solution have been explored (Sch. 40) [187,189-200]. Highly encouraging enantiomeric excesses (ee) on two photoreactions within NaY have been obtained photocyclization of tropolone ethylphenyl ether (Eq. (1), Sch. 40) and Yang cyclization of phenyl benzonorbornyl ketone (Eq. (3), Sch. 40). The ability of zeolites to drive a photoreaction that gives racemic products in solution to ee >60% provides... 

Disilenes react with ketones, aldehydes, esters and acid chlorides by formal [2 + 21-cycloaddition to yield the corresponding disiloxetanes (equation 73)8,16. The reaction is non-concerted and proceeds through the initial formation of a 1,4-biradical intermediate, as has been shown by the products of reaction of tetramesityldisilene (110) with the cyclopropyl aldehyde 117 (equation 90)163. The absolute rate constants listed in Table 19 indicate there to be a significant difference in reactivity between the monophenyl-substituted disilene 103 and the 1,2-diphenyl-substituted derivatives 104, consistent with a steric effect on the rate of formation of the biradical intermediate. As would be expected, no kinetic deuterium isotope effect is discernible from the relative rates of addition of acetone and acetone- to these compounds. 

Chlorocyclophosphazenes react with organic acids or their salts (21, 346, 448), acid amides (206), and acid halides (207) to yield the nitrile of the acid the phosphazene ring is degraded. The reaction of benzoyl chloride with [NP(OEt)2]3 4 gives ethyl chloride, ethyl phos-phenates, and triphenyl-s-triazine (188). The trifluoroethoxy derivatives, [NP(OCH2CF3)2]3 4, react with diphenyl ketone to afford the acid, (CF3CH20)2P(0)(0H), and organic imines (405, 406). 

Easily accessible acetals and ketals of a,p-unsaturated aldehydes and ketones derived fi-om C2-symmetric chiral 1,2-diols have been successfully used with Simmons-Smith reagents furnishing cyclopropane aldehydes with high selectivity and recovery of the auxiliary. Thus, dialkyl tartrates proved to be superior compared to 1,2-diphenyl-ethanediols as chiral auxiliaries in reactions of a,p-unsaturated aldehydes. 

Known also as Diphenyl Ketone. p-Benzoquinone -kwi- non (1,4-benzoquinone, chinone) A yellow crystalline compound used, along with many of its derivatives, as an inhibitor in unsaturated polyester resins to prevent premature gelation during storage. 

Cycloaddition of COj with the dimethyl-substituted methylenecyclopropane 75 proceeds smoothly above 100 °C under pressure, yielding the five-membered ring lactone 76. The regiocheraistry of this reaction is different from that of above-mentioned diphenyl-substituted methylenecyclopropanes 66 and 67[61], This allylic lactone 76 is another source of trimethylenemethane when it is treated with Pd(0) catalyst coordinated by dppe in refluxing toluene to generate 77, and its reaction with aldehydes or ketones affords the 3-methylenetetrahy-drofuran derivative 78 as expected for this intermediate. Also, the lactone 76 reacts with a, /3-unsaturated carbonyl compounds. The reaction of coumarin (79) with 76 to give the chroman-2-one derivative 80 is an example[62]. 

The condensation of thiophene with ketones, under the influence of 70% H2SO4, leads to di-2-thienylmethane derivatives. With acetone, 2,2-di-(2-thienyl) propane (97) is obtained. The condensation of thiophene with dimethyl phenyl carbinol, methyl diphenyl carbinol, and f-butylalcohol, in the presence of SnCU gave (98), (99), and 2,5-di-f-butylthiophene, respectively. Triphenyl carbinol does not... 

The formal relationship between cyclopropenone and an a,a -biscarbene of a ketone (R—C—CO—C—R ) initiated investigations on photolytic and Ag-catalyzed decomposition of a, a -bisdiazo dibenzyl ketone (49) (Trost50 ). Indeed, diphenyl-cyclopropenone was formed in addition to other products (52 and tolane) derived from it furthermore, products resulting from solvent insertion and Wolff rearrangement of the monocarbene 50 were isolated (51) ... 

Whilst Lewis acids like SbCls or A1C13 form stable adducts with diphenyl cyclopropenone, from which the ketone can be regenerated unchanged208, trialkyl boranes effect a remarkable ring expansion to 2-phenyl indenone derivatives 309 containing an additional residue in the 3-position215. ... 

Addition of triethylamine to the oxazaborolidine reaction system can significantly increase the enantioselectivity, especially in dialkyl ketone reductions.79 In 1987, Corey et al.80 reported that the diphenyl derivatives of 79a afford excellent enantioselectivity (>95%) in the asymmetric catalytic reduction of various ketones. This oxazaborolidine-type catalyst was named the CBS system based on the authors names (Corey, Bakshi, and Shibata). Soon after, Corey s group81 reported that another fi-methyl oxazaborolidine 79b (Fig. 6-6) was easier to prepare and to handle. The enantioselectivity of the 79b-catalyzed reaction is comparable with that of the reaction mediated by 79a (Scheme 6-36).81 The -naphthyl derivative 82 also affords high enantioselectivity.78 As a general procedure, oxazaborolidine catalysts may be used in 5-10 mol%... 

With a-hydroxy ketones and their related tosyloxy derivatives. The imidazo [2,T ]thiazole 364 was prepared by acetic acid-catalyzed cyclocondensation of 2-hydroxy-l,2-diphenyl-ethanone with thiophenyl-substituted 2-aminothiazole 363 (Equation 163) <2002MI110>. Under MW irradiation and in the presence of montmorillonite K-10 clay, a mixture of a-tosyloxyketones 365 and 2-imidazolidinethione led to the substituted 5,6-dihydro-imidazo[2,l- ]thiazoles 366 (Equation 164) <1998J(P1)4093>. When using a-tosyloxyacetophenone, prepared by reaction of acetophenone with [hydroxyl(tosyloxy)iodo]benzene (HTIB), 5-aminopyrazole 367 could be converted to imidazo[l,2- ]pyrazole 368 in basic medium (Equation 165) <2005JHC209>. 

When Schiff s bases (242), derived from ketones and tm-butylamine, were reacted with dimethyl methoxymethylenemalonate in diphenyl ether at 80-130°C for 1-15 hr, then at 190-250°C for 1-3 hr, 2-hydroxy-3-pyridinecarboxylates (243) were obtained by a one-pot procedure. In the first step of the reaction, the beta-carbon of the enamine moiety was involved instead of the amino group (89JHC773). 

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