Propanedione 1,3-diphenyl

SYNS OMEGA-BENZOYLACETOPHENONE 2-BENZOYLACETOPHENONE DIBENZOYLMETHANE l,3-DIPHENYL-l,3-PROPANEDIONE KARENZU DK2 1,3-PROPANEDIONE, 1,3-DIPHENYL- RHODIASTAB 83... 

Dibenzoylmethane (l,3-diphenyl-l,3-propanedione) [120-46-7] M 224.3, m 80 . Crystd from pet ether or MeOH. 

If the ligand X2 in a pentacoordinate triorganotin compound is potentially bidentate, such as the anion of l,3-diphenyl-l,3-propanedione or ofiV-benzoyl-N-phenylhydroxylamine, the tin atom is constrained to a cis-RsSnXj type of geometry, e.g., the triphenylstannyl derivatives of... 

It was found that the 1,3-diphenyl-1,3-propanedionate anion behaved as a bidentate ligand whereas the benzoate acted as a monodentate ligand. The Ag-C bonds in 21a and 21b were more or less similar to that found in 18 (21a 2.064(6) A, 21b 2.085(10) A). It is interesting to note that 21b crystallizes as dimers with the presence of short intermolecular Ag-Ag distance of 3.000(10) A, in contrast to the monomeric nature of 21a with a longer Ag-Ag distance of 3.2177(13) A. 

Diphenylphosphorochloridate, d748 1,3-Diphenyl-1,3-propanedione, d68 sym -Diphenylthiourea, 1141 Dipicolinic acid, p270 Di-2-propenylamine, d30... 

Diphenyl-i-butene-i,4-dione, 29 Diphenylhydrazine, 15 Diphenylhydrazine hydrochloride, 15 Diphenylketene, 47 i,3-Diphenyl-i,3-propanedione, 32 Dodecanol, 50... 

PlCOLINIC ACID HYDROCHLORIDE, 79 Potassium acetate, 55 Potassium amide, 91 Potassium bromide, 81, 101 Potassium carbonate, 21 Potassium cyanide, 38, 44 Potassium permanganate, 79 Pressure reaction, 40, 81, ior i,3-Propanedione, i,3-diphenyl-, 32 Propionic acid, /3-3-acenaphthenyl-... 

The plasma half-life of cathinone is 1.5 hours. The primary metabolites are norpseudoephedrine, norephedrine, 3,6-dimethyl-2,5-diphenyl-pyrazine, and l-phenyl-l,2-propanedione (Szendrei 1980 Brenneisen etal. 1986 Guantai and Maitai 1983). However, norpseudoephedrine and norephedrine also originate directly from the leaves, as well as being metabolic products (Widler et al. 1994). Maximal plasma concentrations of norephedrine and norpseudoephedrine are reached at about 3.3 and 3.1 hours, respectively. These two drugs have a much longer duration of action than cathinone, where terminal half-lives could not be calculated after 10 hours. 

Exercise 17-49 Devise a synthesis of diphenylpropanetrione from 1,3-diphenyl-1,3-propanedione, (C6H5CO)2CH2. How could you determine whether the center or one of the flanking carbonyl groups is lost, as carbon monoxide, with aluminum chloride ... 

Polarographic studies on the reduction of 1,3-diphenyl-l, 3-propanedione in 50 % ethanol-water at the mercury cathode in the pH range 4.2 - 13.6 show that this compound is reduced in three successive steps, two one-electron transfers and a two-electron transfer at the most negative potential133 Cpe at either of the two first waves produces pinacolic products, whereas cpe at the third wave produced a good yield of the diol as a meso-dl mixture (Eq. (71) ). 

Recently, a series of studies of the stereoselective reduction of 1,3-diketones has been reported which expands upon this methodology. When 1,3-diphenyl-1,3-propanedione was reduced with three equivalents of NaBH4 in the presence of (S,S)-15,THFA,and ethanol in CHCI3 at -20°C, (S,S)- 1,3-diphenyl- 1,3-propanediol was obtained quantitatively in 97% ee (Scheme 9) [54], The anti syn ratio of the product was 84 16. Diketones with electron-donating and electron-withdrawing substituents on their phenyl rings were also reduced with high enanti-oselectivity and diastereoselectivity. 

The desymmetrization of 2-alkyl-1,3-diketones to the corresponding chiral hydroxyketones was also successfully achieved with the same catalyst system. For example, 2-methyl-l,3-diphenyl-l,3-propanedione was reduced with an equimolar amount of NaBH4 together with THFA and ethanol in the presence of 0.05 equivalents of (R,R)-15 to afford (lk,2S)-2-methyl-3-oxo-1,3-diphenyl-propane (anti syn=99 l) in 99% ee (Scheme 10) [55], 2-Allyl- and 2-benzyl-sub-... 

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