13100-05-5Relevant articles and documents
Novel highly regioselective VO(acac)2/TBHP mediated oxidation of o-alkenyl phenols to o-hydroxybenzyl ketones
Lattanzi, Alessandra,Senatore, Antonello,Massa, Antonio,Scettri, Arrigo
, p. 3691 - 3694 (2003)
A novel mild methodology for the preparation of o-hydroxybenzyl ketones is described starting from o-alkenyl phenols and based on the VO(acac)2/TBHP (2 mol %/1.2 equiv) system. VO(acac)2 first catalyzes the epoxidation of o-alkenyl phenols and then the rearrangement of the epoxyphenols to ketones via the selective benzylic C-O cleavage and 1,2 hydride migration. The protocol has also been applied to set up a useful and easy one-pot conversion of o-alkenyl phenols to benzo[b]furans by means of the sequential addition of TFA, after the generation of the intermediate o-hydroxybenzyl ketones.
Primary kinetic hydrogen isotope effects in deprotonations of a nitroalkane by intramolecular phenolate groups
Backstroma, Nicholas,Burtona, Neil A.,Watta, C. Ian F.
, p. 711 - 722 (2010)
Rate constants and kinetic isotope effects have been determined for the formation of nitronate anions from the ethers 1-(2-methoxyphenyl)-2- nitropropane, 7(X=H, L=H and D) and 1-(2-methoxy-5-nitrophenyl)-2-nitropropane, 7(X=NO2, L=H and D), and from the corresponding phenols, 1-(2-hydroxyphenyl)-2-nitropropane, 3(X=H, L=H and D), and 1-(2-hydroxy-5- nitrophenyl)-2-nitropropane, 3(X=NO2, L=H and D), in aqueous basic medium. For the ethers 7, rates of deprotonation by hydroxide are comparable with those found for deprotonations of 2-nitropropane, with kH/k D (25 °C)=7.7 and 7.8, respectively. In both the cases, the isotope effects are conventionally temperature dependent. For the corresponding phenols 3, conditions have been established under which the deprotonations of the nitroalkane are dominated by intramolecular deprotonation by the kinetically first-formed phenolate anion, with an estimated effective molarity EM ～ 250. For 3 (X=H, L=H or D), kH/kD (25 °C)=7.8, with EaD - EaH =6.9 kJ mol-1 and AH/AD=0.5. For 3(X=NO2, L=H or D), rates of intramolecular deprotonation are reduced 30-fold, and an elevated kinetic isotope effect is found (kH/kD (25 °C)=10.7). Activation parameters (EaD - EaH =17.8 kJ mol-1 and AH/AD=0.008) are compatible with an enhanced tunnelling contribution to reactivity in the H-isotopomer. Copyright
Mechanistic insights into the palladiumII-catalyzed hydroxyalkoxylation of 2-allylphenols
Thiery, Emilie,Chevrin, Carole,Le Bras, Jean,Harakat, Dominique,Muzart, Jacques
, p. 1859 - 1862 (2007/10/03)
The Pd(OCOCF3)2/[(HOCH2CH 2NHCOCH2)2NCH2]2- catalyzed oxidation of o-allylphenol with H2O2 in water/methanol affords a syn and anti mixture of 2-(1,2-dihydroxypropyl)phenol and 2-(2-hydroxy-1-methoxypropyl)phenol. Mechanistic experiments and ESI-MS studies support a pathway wherein isomerization of the C=C bond followed by its epoxidation and oxirane opening led to the products. Recycling of the catalytic system led to gradual lost of activity.
Methods of treating conditions associated with an Edg-2 receptor
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Page/Page column 11; 17, (2008/06/13)
In one aspect, the present invention provides a method for modulating an Edg-2 receptor mediated biological activity in a cell. A cell expressing the Edg-2 receptor is contacted with an modulator of the Edg-2 receptor, which modulates the Edg-2 receptor mediated biological activity. In another aspect, the present invention provides a method for modulating Edg-2 receptor mediated biological activity in a subject. A therapeutically effective amount of an modulator of the Edg-2 receptor is administered to the subject.
Methods of treating conditions associated with an EDG-2 receptor
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Page/Page column 23, (2008/06/13)
In one aspect, the present invention provides a method for modulating an Edg-2 receptor mediated biological activity in a cell. A cell expressing the Edg-2 receptor is contacted with an modulator of the Edg-2 receptor, which modulates the Edg-2 receptor mediated biological activity. In another aspect, the present invention provides a method for modulating Edg-2 receptor mediated biological activity in a subject. A therapeutically effective amount of an modulator of the Edg-2 receptor is administered to the subject.
Mass spectrometric investigations on phenylacetic acid derivatives, IV: Loss of ortho-substituents from ionized phenyl-2-propanones upon electron impact
Striegel,Mayer,Wiegrebe,Schlunegger,Siegrist,Aebi
, p. 751 - 760 (2007/10/02)
In the gas phase, the phenyl-2-propanone molecules 2a-4a lose upon electron impact chloro-, bromo-, and iodo-radicals specifically at the orthopOsition of the phenyl group giving rise to strong (M-Hal.)+-ions (70/12 eV; 1st and 2nd FFR) of identical structure as confirmed by their MIKE-CAD-spectra. The daughter ions at m/z 133 from o-chlorophenyl-2-propanone (2a) and 2,2-dimethyl-2,3-dihydro[b]furane (11) are structurally similar but not identical (similarity index 99.8). The collisionally activated (2nd FFR) (M-Br.)+-ions from o-bromophenyl-2-propanone (3a) and 1-bromo-1-phenyl-2-propanone (12) produce virtually congruent spectra. The most impOrtant subsequent fragmentation of the (M-Hal-)+-ions from 2a-4a is the loss of CO which incorporates the C-atom of the carbonyl group exclusively (13C labelling). Mechanistic aspects of the fragmentation sequences are discussed (Figs. 5 and 8).
REDUCTION PAR LES SELS CHROMEUX DE BROMURES BENZYLIQUES ORTHO-O-ACYLES AVEC TRANSPOSITION DU GROUPEMENT ACYLE DE L'ESTER: ACCES AUX ORTHO-HYDROXYBENZYL CETONES NON MASQUEES ET UNE NOUVELLE PREPARATION DE BENZO(B)FURANNES SUBSTITUES EN POSITION-2
Ledoussal, B.,Gorgues, A.,Coq, A. Le
, p. 5841 - 5852 (2007/10/02)
The ?-bonded organochromium (III) complexes resulting from the reduction of ortho-O-acyl benzylic bromides 1 with CrCl2 undergo an 1,5-transposition of the ester acyl functional group which allows, through selected experimental conditions either a selective access to the unmasked ortho-hydroxybenzyl ketones 2 or a new preparation of the 2-substituted benzofurans 3.The scope and limitations of the method are presented.
Process for producing phenylacetones
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, (2008/06/13)
A phenylacetone or its derivative having the general formula (I): STR1 wherein X, Y, and Z are independently a hydrogen atom, a hydroxyl group, a halogen atom, a nitro group, an amino group, a lower alkyl group having 1 to 6 carbon atoms, a lower alkoxy group having 1 to 6 carbon atoms, or a benzyloxy group and any two substituents of X, Y, and Z may form, together with the benzene ring, a heterocycling ring having 5 to 7 members including 1 or 2 oxygen atoms is produced at a high yield and a high selectivity by reacting a 3-phenylpropylene or its derivative having the general formula (II): STR2 wherein X, Y, and Z are as defined above, with an alkyl nitrite having the general formula (III): wherein R is an aliphatic, aromatic, or alicyclic saturated or unsaturated hydrocarbon group in the presence of (a) water, (b) an alcohol, (c) a palladium catalyst, and (d) an optional amine or copper compound, or by reacting the above-mentioned 3-phenylpropylene or its derivative with the above-mentioned alkyl nitrite in the presence of (a) an alcohol, (b) a palladium catalyst and (c) an optional amine or copper compound to form 1-phenyl-2,2-dialkoxypropane or it derivative having the general formula (IV): STR3 wherein X, Y, Z and R are as defined above, followed by hydrolyzing the reaction product.
Chromium(II) Salt mediated Reductive Transposition of an Ester Acyl Group in ortho-O-Acyl Benzylic Bromides: a Ready Access to Unmasked ortho-Hydroxybenzyl Ketones and a New Route to Benzofurans
Ledoussal, Benoit,Gorgues, Alain,Coq, Andre Le
, p. 171 - 172 (2007/10/02)
The mono-ο-bonded organochromium(III) complexes (A) derived from (1) rearrange internally into (B) through an acyl ester group transposition, selected experimental conditions allowing either a good access to the unmasked ortho-hydroxybenzyl ketones (2) or a new route to the 2-substituted benzofurans (3).
Naturally Occurring Dibenzofurans. Part 4. Synthesis of Dibenzofurandiols by Annelation of Benzofurans
Carvalho, Christopher F.,Sargent, Melvyn V.
, p. 1605 - 1612 (2007/10/02)
Methyl 3-acetylbenzofuran-2-ylacetate (8) undergoes C-methylation affording methyl 2-(3-acetylbenzofuran-2-yl)propionate (13).These compounds and similar oxo esters undergo ready cyclization to dibenzofurandiols on treatment with sodium methoxide in boiling methanol.A convenient synthesis of dimethyl furan-2,5-diylacetate (30) is described, as are attempts to synthesize 1,3,7,9-tetramethoxy-2,8-dimethyldibenzofuran (3).
