L-Hydroxy-5 -methyl-2-phenyl

Anilinocarbonyl-l-hydroxy-4-methyl-2-phenyl-imidazol-3-oxid212 ... 

Kakehi et al. (76JOC1570), in a study of an A-pyridinium A-ylide (270), found that on irradiation it afforded a 15% yield of 6-methyl-2-phenyl-4-azaquinolizin-l-one (274), which is a resonance hybrid of which one of the dipolar structures is that of the betaine of l-hydroxy-6-methyl-2-phenyl-4-azaquinolizinium hydroxide (Scheme 133). The authors suggested a possible mechanism for (271 -+ 274). 

Hydroxy-4-methyl-l-isoindolinone (261, R = H) gave 5-methyl-l(2//)-phtha-lazinone (262) (H2NNH2-H20, H2O, reflux, 16 h 97%) 3-hydroxy-4-methyl-2-phenyl-l-isoindolinone (261, R = Ph) gave the same product... 

CO-NH-C12Hjs -cl 2- (4-Chlor-phenyl) -5-dodecylaminocarhonyl-l-hydroxy-4-methyl-... 97 180... 

In exploring various synthetic methods for the preparation of 1,2-oxaphospholene 2-oxides we investigated the reaction of diacetone alcohol (4-hydroxy-4-methyl-2-pentanone) with methyl and phenylphosphonous dichloride, which was reported (1) to proceed as shown in eq (1) to give 2,3,3,5-tetramethyl-l,2-oxaphos-phol-4-ene 2-oxide or the corresponding 2-phenyl derivative. 

Applications of the Conrad-Limpach reaction to the synthesis of 1-hydroxy-4,7-phenanthrolines or, more correctly, l-oxo-l,4-dihydro-4,7-phenanthrolines, from p-phenylenediamine or 6-amlnoquinolines continue to be reported. l,10-Dihydroxy-3,8-dimethyl-4,7-phenanthroline has again been prepared from p-phenylenediamine, hot diphenyl ether being used to effect the cyclization. Other examples include the new or improved preparations of l-hydroxy-3-methyl-, 10-amino-l-hydroxy-3-methyl-, 2-(y-chlorocrotonyl)- l,10-dihydroxy-3,8-dimethyl-, and 2,9-bis (y- chlorocrotonyl) -1,10- dihydroxy - 3,8 - dimethyl - 4,7 - phenanthro-lines. Compounds prepared in this way have been patented as antiasthmatic agents. A closely related synthesis employing poly-phosphoric acid as cyclizing agent has yielded l-hydroxy-3-phenyl-4,7-phenanthroline. ... 

R3a jj y patej f. A. Vyas, S.P. Pahndey, F. Tavares u. P.S. Fernandes, Synth. Commun. 21, 1583 (1991) mit Hydroxy-(4-methyl-benzolsulfonyloxy)-phenyl-iod und 2,4-Dioxo-3-( 2-phenyl-hydrazi no-methy-len)-pentansaure-ethylcster zu 3-Ethoxycarbonvl-4-hydroxy-l-phenyl-IH-pyrazol (64%). 

Diethoxyphosphoryl-l-hydroxy-ethyl)-4-methyl-2-methylamino- 202 5-(2-Diethoxyphosphoryl-l-hydroxy-propyl)-4-methyl-2-phenyl- 202... 

CijHijNjO, 1.2- Dihydro-l-methyl-2-oxo-3-phenyl 4-oxide 1.2- Dihydro- l-hydroxy-7-methyl-2-oxo- 192-193,196 24, 28... 

A soln. of lOOmg. 4-(l-acetamidoethyl)-5-phenylazotropolone in ethanol refluxed 1.5 hrs. 50 mg. 5-hydroxy-3-methyl-2-phenyl-6(2H)-cyclohepta[c] pyrazolone. 

Hydroxy-4-methyl-5-phenyl-2-pyridone and sodium nitrite in sulfuric acid give 2-hydroxy-4methyl-5-phenyl-l-azaquinone (XII-457). ... 

Hydroxy-4-methyl-5-phenyl-l-azaquinone, from 3-hydro,xy-... 

Anhydro-5-hydroxy-3-methyl-2-phenyl-l,3,4-thiadiazolium hydroxide, in common with related mesionic systems (see pp. 615 and 719), may be 0-alkylated by triethyloxonium fluoroborate to yield the quaternary salt (216) this is reconverted into the mesionic starting material above its melting point." ... 

Among the products formed when 2-amino-5-hydroxy-4-methyl-3-phenyl-pyridine is treated with nitrous acid is a compound G12H9O3N. This is also formed when another of the products, 2,5-dihydroxy-4-methyl-6-nitroso-3-phenylpyridine, is hydrolysed, and it is clearly 2-aza-3-hydroxy-5-methyl-6-phenyl-l,4-benzoquinone (or a tautomer of this structure)... 

A soln. of 4-hydroxy-4-methyl-5-phenyl-2-pentanone in 48%-HBr-glacial acetic acid heated 2 hrs. on a steam bath 1,3-dimethylnaphthalene. Y 87-90%. -The above mixture of HBr and acetic acid (Bradsher s reagent) gave higher yields than other acids. F. e. s. P. Ganonne, P. Holm, and L. G. Leitch, Gan. J. Ghem. 45, 2151 (1967). 

Indolizine, hydroxy-conformations, 4, 451 GLC retention times, 4, 451 synthesis, 4, 121 tautomerism, 4, 198, 452 Indolizine, 2-hydroxy-synthesis, 4, 463 Indolizine, 8-hydroxy-conformation, 4, 452 Indolizine, 2-hydroxymethyl-synthesis, 4, 461 Indolizine, 3-hydroxymethyl-synthesis, 4, 461 Indolizine, 6-hydroxymethyl-synthesis, 4, 461 Indolizine, methyl-mass spectra, 4, 187, 450 NM 4, 448 Indolizine, 2-methyl-diazo coupling, 4, 454 mass spectra, 2, 529, 4, 450 nitration, 4, 50, 454 nitrosation, 4, 454 reaction with diaryl disulfide, 4, 460 reaction with nitroethane, 4, 460 Indolizine, 3-methyl-basicity, 4, 454 Indolizine, 5-methyl-acidity, 4, 461 synthesis, 4, 466 Indolizine, 6-methyl-mass spectra, 4, 450 Indolizine, l-methyl-2-phenyl-nitration, 4, 454 nitrosation, 4, 454, 455 Indolizine, 3-methyl-2-phenyl-reaction... 

Methyl-2-phenyl-4-athoxycarbonyl-l,5-dihydro-l,3-oxazol wird je nach Menge Li-thiumalanat entweder selektiv zum Alkohol reduziert oder man erhalt unter Ringspaltung 2-Benzylamino-3-hydroxy-butandiol-(1,3) (s. S. 347). 

Jod-5-hydroxy-4-methoxy-phenyl)- -nitril 118 [l-Methyl-2-phenyl-indolyl-(3)]- -dimethylamid 321... 

Hydroxy-6,7-methylendioxy-3-methyl-l-(3,4,5-trimethoxy-phenyl)-2-carboxy- 318 f. 

A convenient route to 2-alkylthio-4-alkyl-4-hydroxy-5,6-dihydro-4/7-l,3-thiazine derivatives 176 is the reaction of A-alkyldithiocarbamates with a,/3-unsaturated ketones in the presence of boron trifluoride etherate at 0°C (Scheme 15) <2002HAC377>. The predominant diastereomer displayed a m-relationship between the hydroxyl group and the C-4 substituent. Subsequent dehydration led to two isomeric products 177 and 178 with an equilibrium mixture resulting in a ratio of 94 6 in the case of 2-benzylthio-4-hydroxy-4-methyl-5,6-dihydro-4/7-l,3-thiazine. 2-Phenyl-4-alkyl-4-hydroxy-5,6-dihydro-4/7-l,3-thiazine derivatives are similarly prepared by reacting thio-benzamide with o ,/3-unsaturated ketones at room temperature <2002EJP307>. 

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