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Pyridines ethoxycarbonylation

The high reactivity of the exocyclic 4-NH- group is again illustrated by the reaction of 2-imino-3-phenyl-4-amino-5-(ethoxycarbonyl)-4-thiazoline with EtOjCCH SCN, which yields 134 (296), and by the intramolecular preparation of the dihydrothiazolo[4,5-h]pyridine derivative 136 (297) (Scheme 89). [Pg.58]

Pyra20lo[3,4-i]pyridine electron density, 5, 306 (69CJC1129) Pyrazolo[3,4-i]pyridine, 4-chloro-5-ethoxycarbonyl-1-ethyl-... [Pg.49]

Imidazo[4,5-6]pyridin-5(4H)-one, 6-ethoxycarbonyl-3-methyl-2( 1 H)-thioxo-synthesis, 5, 639... [Pg.662]

Thieno[2,3-c]pyridine, 2-amino-6-benzyl-3-ethoxycarbonyl-4,5,6,7-tetrahydro-biological activity, 4, 1015 Thieno[2,3-c]pyridine, 4,5,6,7-tetrahydro-biological activity, 4, 1015 Thieno[3,2-6]pyridine, 3-hydroxy-synthesis, 4, 1010... [Pg.879]

Treatment of alkyl 9-benzyloxycarbonyl-3-methyl-6-oxo-2/7,6//-pyr-ido[2,l-f ][l,3]thiazine-4-carboxylates with BBr3 in CH2CI2 at -70 °C for 0.5-1 h and at room temperature for 3h yielded 9-carboxyl derivatives. The decarboxylation of these acids was unsuccessful. Hydrolysis of diethyl cA-3,4-H-3,4-dihydro-3-methyl-6-oxo-2//,6//-pyrido[2,l-f ][l,3]thiazine-4,9-dicarboxylate in aqueous EtOH with KOH at room temperature for 3 days yielded 4-ethoxycarbonyl-3,4-dihydro-3-methyl-6-oxo-2//,6//-pyrido-[2,l-f ] [1,3]thiazine-9-carboxylic acid (00JCS(P1)4373). Alkyl 9-hydroxy-methyl-3-methyl-6-oxo-3,4-dihydro-2//,6//-pyrido[2,l-f ][l,3]thiazine-4-car-boxylates were O-acylated with AC2O and (PhC0)20 in pyridine at room temperature for 12-48h. [Pg.192]

A solution of 1-benzyl-4-piperidone, ethyl cyanoacetate, powdery sulfur and morpholine in ethanol is heated moderately under reflux for about 20 minutes to dissolve the powdery sulfur. The mixture is heated under reflux for one further hour to complete the reaction. On standing at room temperature, the mixture yields a precipitate. The precipitate is collected by filtration, washed well with methanol and recrystallized from methanol to give 2-amino-6-benzyl-3-ethoxycarbonyl-4,5,6,7-tetrahydrothieno(2,3-c)-pyridine as almost colorless needles melting at 112° to 113°C. [Pg.1493]

Treatment of 25 and 26, respectively, in pyridine with equimolar amounts of benzyloxycarbonyl chloride at low temperature, followed by addition of an excess of ethoxycarbonyl chloride, yielded the corresponding methyl 5-0-(benzyloxycarbonyl)-2-0-(ethoxycarbonyl)-/3-(57) and -a-D-glucofuranosidurono-6,3-lactone (58). Hydrogenolysis of the benzyloxycarbonyl group resulted in formation of methyl 2-0-(ethoxycarbonyl)-/ - (59) (70%) and -a-D-glucofuranosidurono-6,3-lactone (60) (30%), respectively, both in crystalline form. The /3-D... [Pg.205]

MethyM-cthoxycarbonyl-5-bcnzoyl-hydrazino-l //-pyrazole 274, prepared by reacting benzoyl chloride and 3-methyM-cthoxycarbonyl-5-bcnzoyl-hydrazino-l //-pyrazole hydrochloride 273, in the presence of pyridine in acetonitrile, has been cyclized with phosphoryl chloride in benzene or toluene to give 7-ethoxycarbonyl-6-methyl-3-phenyl-l //-pyrazolo[5,l -/ 1,2,4 triazolc 55. This compound has been also synthesized through cyclization of... [Pg.249]

Cyclopropylamino)-5-fluoro-6-(4-ethoxycarbonyl-l-piperazinyl)-pyridine was reacted with isopropylidene methoxymethylenemalonate (420) in methanol at ambient temperature for 4 hr to give isopropylidene 2-pyridylaminomethylenemalonate (428) in 67% yield (85EUPI53I63, 85EUP153828, 85EUP159I74 86EUP17265I 88EUP265230). [Pg.111]

In only a few cases are ring transformation reactions found in which a in-termolecular CCC transfragment reaction occurs. An example of this rearrangement has been observed in the reaction of 3,5-dinitropyridin-4(l//)-one (99) with diethyl sodio-3-oxopentanedioate. It provided in good yield 3,5-di(ethoxycarbonyl)pyridin-4-(lH)-one (102) and 1,3-dinitroacetone as second product (78H108). Its structure was proven by the formation of l-phenyl-3-nitro-4-hydroxy-5-phenylazopyrazole (103), obtained on heating of the diphenylhydrazone of 1,3-dinitroacetone (Scheme III.53). [Pg.136]

Other chemical reagents that have been used to dehydrogenate are diphenyl disulfide for 1,2,3,4-tetrahydrocarbazole itself, N-bromosuccinimide in pyridine for 1-ethoxycarbonyl-1,2,3,4-tetrahydrocarbazole, selenium dioxide for 9-methyl-1,2,3,4-tetrahydrocarbazole (a 1 5 mixture of 9-methyl-carbazole and 1-oxo-1,2,3,4-tetrahydrocarbazole was obtained ), and manganese dioxide to aromatize 1-methyl- and l,4-dimethyl-6-alkoxy-3-formyl-1,2,3,4-tetrahydrocarbazoles and 1,9-diprenyl-1,4-dihydrocarba-zole. ... [Pg.163]

To complete the section on the synthesis of 4,4 -bipyridines, we summarize the methods reported for the preparation of some substituted 4,4 -bi-pyridines and 4,4 -bipyridinones. These methods are closely analogous to syntheses already discussed for some of the isomeric bipyridines. Thus the Hantzsch reaction using pyridine-4-aldehyde, ethyl acetoacetate, and ammonia gives 3,5-di(ethoxycarbonyl)-1,4-dihydro-2,6-dimethyl-4,4 -bipyridine, which after oxidation, followed by hydrolysis and decarboxylation, afforded 2,6-dimethyl-4,4 -bipyridine. Several related condensations have been reported. Similarly, pyridine-4-aldehyde and excess acetophenone gave l,5-diphenyl-3-(4-pyridyl)pentane-l,5-dione, which with ammonium acetate afforded 2,6-diphenyl-4,4 -bipyridine. Alternatively, 1-phenyl-3-(4-pyridyl)prop-2-enone, A-phenacylpyridinium bromide, and ammonium acetate gave the same diphenyl-4,4 -bipyridine, and extensions of this synthesis have been discribed. Condensation of pyridine-4-aldehyde with malononitrile in the presence of an alcohol and alkaline catalyst produced compounds such as whereas condensations of... [Pg.330]

Reaction of the quaternized salts of 4-ethoxycarbonyl-3,5-dimethyl-f-phenylpyttolo(furo or thieno)[2,3-c]pyrazole 34 with the iodomethane quaternary salts of pyridine, quinoline, and isoquinoline in ethanol with catalytic piperidine gave 3-[4(f)]-monomethine cyanine dyes (e.g., 35). Additionally, 3-[2(4)]-trimethine cyanine dyes and 4-[2(4)]-di-3[2(4)]-tri-mixed methine cyanine dyes (e.g., 36 and 37, respectively) were similarly prepared from the intermediates derived by reaction of 34 with triethyl orthoformate in the presence of piperidine (Scheme 8) <2002CCS106f>. [Pg.71]

The synthesis of 6-substituted derivatives 626 was achieved via reaction of 2-substituted-5-aminopyridine-4-car-boxylic acids and formamidine acetate in boiling 2-methoxyethanol <1996J(P1)2221>. The pyrido[3,4- lpyrimidinone 628 was prepared by amination of the thioureido derivative 627 with diisopropylamine followed by cyclization in boiling DMF <2004FRP2846657>. Pyridine 627 was prepared from the corresponding 3-amino derivative with ethoxycarbonyl isothiocyanate in DMF. [Pg.827]

Die thermische Cyclisierung von 2-(Ethoxycarbonyl-amino)-pyridin-l-oxidcn durch Erhitzen auf 140-150" fiihrt zu kondensierten 1,2,4-Oxadiazoleni91 ... [Pg.467]

Durch thermische Cyclisierung von 4-(2-Ethoxycarbonyl-hydrazinocarbonyl)-pyridin (155-165° 40 -50 min) erhalt man 2-Hydroxy-5-(2-pyridyl)-l,3,4-oxadiazol nur in einer Ausbeute von 40%176 (vgl. S. 535). [Pg.538]


See other pages where Pyridines ethoxycarbonylation is mentioned: [Pg.132]    [Pg.132]    [Pg.67]    [Pg.49]    [Pg.787]    [Pg.217]    [Pg.35]    [Pg.36]    [Pg.53]    [Pg.152]    [Pg.2294]    [Pg.716]    [Pg.135]    [Pg.190]    [Pg.470]    [Pg.21]    [Pg.204]    [Pg.252]    [Pg.874]    [Pg.137]    [Pg.518]    [Pg.789]    [Pg.232]    [Pg.106]    [Pg.23]    [Pg.152]    [Pg.245]    [Pg.440]    [Pg.443]    [Pg.494]    [Pg.507]    [Pg.567]    [Pg.229]   
See also in sourсe #XX -- [ Pg.272 ]




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4 -ethoxycarbonyl

Ethoxycarbonylation

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