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Dimethyl- -6-formyl-2,10,14-trimethyl

Dimethyl- -formyl-azulen169 3-Formyl-l,4,7-trimethyl-azulen169 1 -Formyl-4,6,8-trimeth y l-azulen1 h R / - Formyl-2,4,6,8-tetramethyl-azulen172... [Pg.43]

Analog erhalt man aus Trimethyl-formyl-hydrazin Tetramethyl-hydrazin (55% d.Th. Kp 71-72°). Die Reduktion von l,2-Dimethyl-l,2-diformyl-hydrazin ergibt nur 15% d.Th. Tetramethyl-hydrazin5 (zur Arbeitsvorschrift s. ds. Handb., Bd. X/2, S. 50). [Pg.258]

Dimethyl-4-athyl-2-formyl-pyrrol —> 2,3J-Trimethyl-4-athyl-pyrrol13 49% d.Th. [Pg.290]

In a similar manner, 2,2,4-trimethyl-27/,677-pyrimido[2,T4][l,3]thiazines with 7-formyl, 7-acetyl, or 7-C02Me substituents were obtained in good to excellent yields by reacting Ar,Ar-dimethyl-Ar -(4,6,6-trimethyl-6//-l,3-thia-zin-2-yl)formamidine with acrolein, methyl vinyl ketone, or methyl acrylate, respectively <2002S403>. [Pg.308]

It is of course possible to name individual radialenes according to IUPAC rules [e.g. per(methylene)cycloalkanes 1-4]. However, the descriptiveness of the term radialene may some day pave its way into the official nomenclature. For substituted [ ]radialenes we have proposed1 a pragmatic numbering system, in which an inner ring is numbered first, followed by an outer ring . The numbering of substituents should follow IUPAC rules. Thus, the hydrocarbon 7 is 4,4-diethyl-5,5-dimethyl[3]radialene, the ester 8 should be called 7-methoxycarbonyl-5,5-dimethyl[4]radialene, the nitrile 9 which can exist in four diastereomeric forms is (6Z,7Z)-6-cyano-5,5,7-trimethyl[4]radialene and the difunctionalized [5]radialene 10 is (7 ,6Z)-7-bromo-6-formyl-6-methyl[5]radialene. [Pg.928]

Vilsmeier formylation of carbazole can be conducted to give good yields of 3-monoformylcarbazoles 9-methyl, 9-ethyl, 9-n-butyl, 9-isoamyl, and 9-isobutyl derivatives were made in this way. The C-form-ylation of various carbazoles required for alkaloid and alkaloid analog synthesis makes instructive reading 1,4-dimethyl-, - 1,4,6-trimethyl-, - 1,4,9-trimethyl-, 1,4-diraethyl-6,7-methylenedioxy-, l,4-dimethyl-6,7-dimethoxy-, l,4-dimethyl-8-methoxy- (some N-formylation also obser-... [Pg.138]

Formyl-2-methylfuran was converted in 75% yield into derivative 319 by electrolytic methoxylation. A corresponding mixture of cis-diols (320) was treated with Dowex W-50 ion-exchange resin in methanol for four days, to afford 5-deoxy-3-C-(dimethoxymethyl)-DL-eryf/rro-4-pentulose dimethyl acetal (321). Reduction of this compound with lithium aluminum hydride or sodium borohydride gave a mixture of 5-deoxy-3-C-(dimethoxymethyl)pentoses, which was separated by column chromatography on silica gel, to give206 DL-streptose tetramethyl acetal (322) and the isomeric 5-deoxy-3-C-(dimethoxy-methyl)-DL-ribose dimethyl acetal 323 (hjxo ribo = 13 7). Detailed, combined gas-liquid chromatographic-mass spectrometric analysis of the compounds related to streptose (in the form of their trimethyl-silyl derivatives) has been described.207... [Pg.64]

N-Heterocycles Pyridine Pyrazines Unsubstituted, 2,3-Dimethyl, MARM ++ 2,5-Dimethyl-3-ethyl, Methyl, 2-Ethyl-6-methyl, 2,5-Dimethyl, 2-Ethyl-5-methyl, 2,6-Dimethyl, Acetylmethyl, 2-(2-Furyl), Ethyl, 2-Methyl-5-(methylethyl), Trimethyl Pyrroles 2-Acetyl, N-Methyl-2-furyl, 1-Formyl, 1-Furfury 1-2-formyl, 5-Methvl-2-formvl Trimethylpyrazine (TMPy) (RV = 0.989)... [Pg.127]

One method for the synthesis of hydroxyalkyl-substituted P-lactams is by the Staudinger reaction, the most frequently used method for the synthesis of P-lactams.86 This method for the preparation of 4-acetoxy- and 4-formyl-substituted P-lactams involves the use of diazoketones prepared from amino acids. These diazoketones are precursors for ketenes, in a diastereoselective, photochemically induced reaction to produce exclusively tram-substituted P-lactams. The use of cinnamaldimines 96, considered as vinylogous benzaldimines, resulted in the formation of styryl-substituted P-lactams. Ozonolysis, followed by reductive workup with dimethyl sulfide, led to the formation of the aldehyde 97, whereas addition of trimethyl orthoformate permitted the production of the dimethyl acetal 98 (Scheme 11.26). [Pg.181]

Successive reduction of l,3-dimethyl-4,5,6,7-tetrahydrobenzo[c]-thiophen-4-one (Section III,C) with sodium borohydride and dehydration of the resulting alcohol with polyphosphoric acid gives the unstable 1,3-dimethyl derivative [(18) R = H] in excellent yield,35 and successive treatment of the same ketone with methylmagnesium iodide and acid gives the 1,3,7-trimethyl derivative [(18) R=Me] (Table IV) and a second compound which is reported to be a dimer. 36 When l,3-dimethyl-4,5,6,7-tetrahydrobenzo[c]thiophen-4-one is treated with a mixture of phosphorus oxychloride and dimethyl-formamide (Vilsmeier-Haack formylation), it gives compound 19, which yields 20 on being treated successively with thioglycolic acid... [Pg.341]

In attempts to prepare 3-acyl-substituted BIPS (113), various salicylaldehydes were condensed with l,3,3-trimethyl-2-formylmethyleneindoline (Fischer s aldehyde). In alcohol, dimethylformamide, tetrahydrofuran, Y-mcthylpyrrolidonc. and hexamethylphosphoramide as the sole solvents, decarbonylation occurred and the only products were the BIPS compounds. However, in dimethyl sulfoxide, 5-nitro-and 3-bromo-5-nitrosalicylaldehydes gave 11 and 5.6% of the desired 3-formyl-BIPS, respectively. The structures were assigned from their IR and NMR spectra. [Pg.48]

Enol ethers of alkyl cyclopropyl ketones are alkylated or carboxylated under the correct conditions. Methyl ann, c ,cw-2,9,9-trimethyl-5-trifluoromethylsulfonyloxytricyclo[5.3.0.0 " ]dec-5-ene-4-carboxylate on treatment with palladium(II) acetate in methanol containing triethylamine under a carbon monoxide atmosphere resulted in diester formation giving dimethyl fln ,c .5,cw-2,9,9-trimethyltricyclo[5.3.0.0 ]dec-5-ene-4,5-dicarboxylate in excellent yield (93%). The same substrate was converted to methyl anr/,cw,d. -5-formyl-2,9,9-trimethyltricyclo[5.3.0.0 ]dec-5-ene-4-carboxylate in 88% yield on carbonylation in the presence of tetrakis(triphenylphosphane)palladium, tributyltin hydride, and lithium chloride. ... [Pg.1765]

H-5,6-Dihydro-ds-4,5-dimethyl 6-Acetyl-4H -5,6-dihydro-2-methyl 6-Formyl-4H-5,6-dihydro-c s-4,5-dimethyl 4H-5,6-Dihydro-2,(cis)4,5-trimethyl, Me... [Pg.688]

The synthesis pathway started with the lithiation of ethylbenzene 121 at the benzylic position, followed by acylation of the toluate anirni intermediate at low temperature. It is noteworthy that a potentially competing orf/io-lithiati(Mi of the type championed by Snieckus 85) i.e. between the two stabilizing methoxyl radicals) was not reported under these conditions. Subsequent reduction of benzyUcetone 122 provided smooth access to the t/irco-dimethyl-substituted bicy-clic intermediate 123 via lactonization. DIBAL reduction (—> 124) and reductive debenzylation with palladium on charcoal gave the ring-opened alcohol 125, which was further demethylated to provide a 1,3-diphenol, and then carboxylated under buffered conditions to yield acid 117, also known as phenol B . This compound was formylated with trimethyl orthoformate and acid, then cyclized to give the quinone structure and natural product, 116 (Scheme 3.1). [Pg.25]

I1CIO2P4C13H32, Iridium(l+), (carbondioxide)-bis[ 1,2-ethanediylbis(dimethyl-phosphine)]-, chloride, 21 100 IrC104P3CiiH27, Iridium, chloro[(formyl-KC-oxy)formato-KO-(2 - )]tris-(trimethylphosphine)-, 21 102 IrCIP3C 7H4i, Iridium, chloio(ti -cyclo-octene)tris( trimethyl-phosphine)-, 21 102... [Pg.270]


See other pages where Dimethyl- -6-formyl-2,10,14-trimethyl is mentioned: [Pg.281]    [Pg.258]    [Pg.906]    [Pg.237]    [Pg.139]    [Pg.149]    [Pg.134]    [Pg.35]    [Pg.37]    [Pg.240]    [Pg.281]    [Pg.294]    [Pg.34]    [Pg.232]    [Pg.240]    [Pg.419]    [Pg.281]    [Pg.775]    [Pg.297]    [Pg.219]    [Pg.270]    [Pg.117]    [Pg.724]    [Pg.2114]    [Pg.117]   


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2.4- Dimethyl-5-formyl

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