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Heterocycles containing

The compounds of this article, ie, ftve-membered heterocycles containing two adjacent nitrogen atoms, can best be discussed according to the number of double bonds present. Pyrazoles contain two double bonds within the nucleus, imparting an aromatic character to these molecules. They are stable compounds and can display the isomeric forms, (1) and (2), when properly substituted. Pyrazoles are scarce ia nature when compared to the imidazoles (3), which are widespread and have a central role ia many biological processes. [Pg.305]

Scheme 1 General reaction schemes tor the synthesis of five-membered heterocycles containing two or more heteroatoms by aldol-related reactions... Scheme 1 General reaction schemes tor the synthesis of five-membered heterocycles containing two or more heteroatoms by aldol-related reactions...
As shown in Scheme 2, two heteroatom-carbon bonds are constructed in such a way that one component provides both heteroatoms for the resultant heterocycle. By variation of X and Z entry is readily obtained into thiazoles, oxazoles, imidazoles, etc. and by the use of the appropriate oxidation level in the carbonyl-containing component, further oxidized derivatives of these ring systems result. These processes are analogous to those utilized in the formation of five-membered heterocycles containing one heteroatom, involving cyclocondensation utilizing enols, enamines, etc. [Pg.118]

Dipolarophiles utilized in these cycloadditions leading to five-membered heterocycles contain either double or triple bonds between two carbon atoms, a carbon atom and a heteroatom, or two heteroatoms. These are shown in Scheme 9 listed in approximate order of decreasing activity from left to right. Small rings containing a double bond (either C=C or C=N) are also effective dipolarophiles, but these result in six- and seven-membered ring systems. [Pg.143]

Any heterocycle containing the OCH=CH moiety can in principle extrude the superfluous fragment and form oxirene, as illustrated for a five-membered ring in Scheme 105. Probably the most propitious AB fragment would be nitrogen, but the required 1,2,3-oxadiazole (123) is unknown (see Chapter 4.21), probably because of ready valence tautomerization to diazoethanal (Scheme 106) (this approach has been spectacularly successful with the sulfur analogue of (2) (8UA486)). The use of (123) as an oxirene precursor is thus closely linked to the important diazo ketone decompositions discussed in Section 5.05.6.3.4(f). [Pg.128]

IV. Heterocycles Containing Other Elements in the Ring along with Te and N Atoms... [Pg.31]

The reactions of diazomethane with heterocycles containing a ketonic grouping in the ring do not differ, in principle, from those of alicyclic ketones (see footnotes 3 and 177) ring expansion and the formation of epoxides compete. In general, ring expansion is the more important reaction for example, tetrahydropyran-4-one (99) is converted to l-oxacycloheptan-4-one (100) (60%) and 4,4 -epoxy-4-methyltetrahydropyran (101) (23%). ... [Pg.282]

These intramolecular IHDA pyrimidine-to-pyridine ring transformations are also successfully applied to synthesize bicyclic heterocycles, containing a... [Pg.56]

Thus, most ionic liquids are formed from cations that do not contain acidic protons. A summary of the applications and properties of ionic liquids may be found in a number of recent review articles [3]. The most common classes of cations are illustrated in Figure 2.1-1, although low melting point salts based on other cations, such as complex poly cationic amines [4] and heterocycle-containing drugs [5], have also been prepared. [Pg.8]

However, heterocycles containing thiophenols have not been reported. It has been observed that the thiophe-nolate ion undergoes nucleophilic attack by the halo/ nitro compounds more easily than the phenolate ion in displacement reactions [37-39]. The experimental result shows that the reactivity of 3-nitro-N-phenyl-phthali-mide with 4-methyl-thiophenolate (reaction 1) is 100 times faster than that of 4-methyl phenolate [40] (reaction 2) ... [Pg.37]

Similarly, the other new heterocycle containing poly (aryl ethers) have been synthesized by many researchers... [Pg.39]


See other pages where Heterocycles containing is mentioned: [Pg.666]    [Pg.108]    [Pg.253]    [Pg.297]    [Pg.18]    [Pg.131]    [Pg.138]    [Pg.8]    [Pg.23]    [Pg.124]    [Pg.150]    [Pg.666]    [Pg.10]    [Pg.167]    [Pg.250]    [Pg.259]    [Pg.508]    [Pg.314]    [Pg.285]    [Pg.2]    [Pg.2]    [Pg.201]    [Pg.270]    [Pg.100]    [Pg.48]    [Pg.145]    [Pg.118]    [Pg.254]    [Pg.192]    [Pg.32]    [Pg.1151]    [Pg.15]   
See also in sourсe #XX -- [ Pg.1147 ]

See also in sourсe #XX -- [ Pg.1147 ]




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Acetylenecarboxylic esters, reactions with nitrogen-containing heterocycles

Acetylenecarboxylic esters, reactions with nitrogen-containing heterocycles through nucleophilic additions

Antioxidative activity, sulfur-containing heterocyclic compounds formed

Aromatic heterocyclic containing

Aryltelluroformates as precursors of selenium-containing heterocycles

Benzene-fused heterocycles containing tellurium, selenium and sulphur

Boron-containing heterocyclic

Boron-containing heterocyclic carbenes

Chiral nitrogen-containing heterocycles

Cobalt-containing heterocycles

Compounds containing Three or Four Fused Heterocyclic Rings (5,5,5), (5,5,6), (5,5,7), (5,6,7), and

Conducting polymers containing heterocyclic units

Dibenzo Heterocycles Containing One Ring Nitrogen Atom

Electrochemical fluorination containing heterocycles

Ferrocenes Containing a Heterocyclic Ring Fused to the Ferrocene

Five-Membered Heterocycles Containing One Heteroatom

Five-Membered Heterocycles Containing Two Heteroatoms

Five-membered Heterocycles containing One Heteroatom Pyrrole, Furan and Thiophene

Fluorine-containing Substituents into Five-Membered Heterocycles via Dipolarophiles

Fluorine-containing Substituents into Five-Membered Heterocycles via Fluoro-substituted 1,3-Dipoles

Fluorine-containing heterocycles, Part

Formation of Heterocycles Containing Nitrogen and Oxygen

Four-membered Heterocycles containing a Single Nitrogen, Oxygen or Sulfur Atom

Fused Heterocycles containing One Oxygen or Sulphur Atom

Fused to other Nitrogen-containing Heterocycles

Heterocycle-containing compounds

Heterocycles Containing Azide Groups

Heterocycles Containing B-E Linkages

Heterocycles Containing Four-Coordinate Annular Boron

Heterocycles Containing More Than Two Hetero Atoms

Heterocycles Containing More Than Two Heteroatoms

Heterocycles Containing Nitrogen, Oxygen, and Sulphur

Heterocycles Containing Other Elements in the Ring along with Te and N Atoms

Heterocycles Containing Tin-Group 14 Element Bonds

Heterocycles Containing Tin-Transition Element Bonds

Heterocycles Containing Unusual Heteroatoms

Heterocycles Containing a Ring-Junction Nitrogen (Bridgehead Compounds)

Heterocycles Containing a Ring-junction Nitrogen

Heterocycles boron-containing

Heterocycles chalcogen-containing

Heterocycles containing One Sulphur Atom

Heterocycles containing Other Atoms

Heterocycles containing Phosphorus (with or without Oxygen)

Heterocycles containing Two Oxygen Atoms

Heterocycles containing Two Sulphur Atoms

Heterocycles containing an Oxygen Atom in each of

Heterocycles containing both oxygen and sulfur in the same ring

Heterocycles containing more than One Heteroatom

Heterocycles containing one oxygen atom

Heterocycles containing one sulfur atom

Heterocycles containing the sulfamide moiety

Heterocycles containing two or more oxygen atoms

Heterocycles containing two or more sulfur atoms

Heterocycles natural products containing

Heterocycles nitrogen containing, acridine

Heterocycles oxygen containing, furan

Heterocycles phosphorus-containing

Heterocycles saturated, sulfur containing

Heterocycles selenium-containing

Heterocycles sulfur containing, reactions

Heterocycles sulfur containing, thiophene

Heterocycles tellurium-containing

Heterocycles, N-containing

Heterocyclic Carbenes Containing Boron within the Heterocycle

Heterocyclic Compounds Containing Nitro Groups

Heterocyclic Ring-Containing Oligomers

Heterocyclic compounds containing carbonyl groups, chemistry

Heterocyclic compounds sulfur-containing, preparation

Heterocyclic sulfur-containing compounds

Heterocyclic synthesis nitrogen-containing

Heterocyclic synthesis oxygen-containing

Heterocyclic systems, pyridine-containing

Heterocyclics, containing phosphorus

Homopolymers and alt-copolymers containing heterocyclic Groups

Indoles polycyclic heterocycles containing

Iron-Catalyzed Synthesis of Nitrogen-Containing Heterocycles

Iron-Catalyzed Synthesis of Oxygen-Containing Heterocycles

Iron-containing heterocycles,

Large oxygen containing heterocycles

Manganese-containing heterocycles

Medium-sized-ring Nitrogen-containing Heterocycles

Medium-sized-ring Oxygen-containing Heterocycles

Nickel-containing heterocycles

Nitrogen heterocycles containing carbonyl

Nitrogen heterocycles containing carbonyl groups, unsaturated, chemistry

Nitrogen- and Sulphur-containing Heterocycles

Nitrogen-containing heterocycle synthesis

Nitrogen-containing heterocycle synthesis compounds

Nitrogen-containing heterocycle synthesis five-membered ring heterocycles

Nitrogen-containing heterocycle synthesis seven-membered ring heterocycles

Nitrogen-containing heterocycles

Nitrogen-containing heterocyclic compounds

Nitrogen-containing heterocyclic systems

Nitrogen-containing heterocyclics

Of metal-containing heterocycles

Of nitrogen-containing heterocycles

Of oxygen- and sulfur-containing heterocycles

Of unsaturated nitrogen heterocyclic compounds containing carbonyl

Other Five-Membered Oxygen-Containing Heterocycles

Other N-containing Heterocycles

Oxygen containing heterocycles coumarin

Oxygen containing heterocycles dihydropyran

Oxygen containing heterocycles functionalization

Oxygen- and Sulphur-containing Heterocycles

Oxygen-Containing Heterocyclic Compounds

Oxygen-containing heterocycle reaction

Oxygen-containing heterocycle synthesis

Oxygen-containing heterocycle synthesis compounds

Oxygen-containing heterocycles

Oxygen-containing heterocycles metathesis

Oxygen-containing heterocycles photochemistry

Oxygen-containing heterocyclics

Palladium nitrogen-containing heterocycles

Palladium oxygen containing heterocycles

Palladium sulfur-containing heterocycles

Pd-Catalyzed Synthesis of Nitrogen-Containing Heterocycles

Pd-Catalyzed Synthesis of Other Heteroatom-Containing Heterocycles

Pd-Catalyzed Synthesis of Oxygen-Containing Heterocycles

Perfluorinated nitrogen-containing heterocycles

Photochemistry of nitrogen-containing heterocycles

Photochemistry of oxygen- and sulfur-containing heterocycles

Poly containing heterocyclic units

Poly containing heterocyclic units, synthesis

Poly(methacrylate)s Containing Heterocyclic Side Groups

Polyesters aromatic heterocycle containing

Polymers Containing Heterocycles in the Backbone

Polymers, conducting containing heterocycle units

Pseudobases of Metal Complexes Containing Heterocyclic Ligands

Radicals Containing a Five-Membered Heterocycle

Radicals Containing a Six-Membered Heterocycle

Reactive Polymers Containing Heterocyclic Groups

Reduction of Heterocycles Containing One Nitrogen Atom

Reduction of Heterocycles Containing Three Nitrogen Atoms

Reduction of Heterocycles Containing Two Nitrogen Atoms

Reduction of Non-aromatic Heterocycles Containing the C N Function

Reductions of Other Heterocycles Containing One Nitrogen Atom

Rh-Catalyzed Synthesis of Nitrogen-Containing Heterocycles

Rh-Catalyzed Synthesis of Oxygen-Containing Heterocycles

Rhenium-containing heterocycles

Rhodium oxygen containing heterocycles

Selenium and tellurium containing heterocycles

Seven-membered heterocycle-containing

Silicon containing heterocycles

Silver nitrogen-containing heterocycle

Silver-Catalyzed Synthesis of Nitrogen-Containing Heterocycles

Six-membered ring heterocycles containing one oxygen atom

Sulfamide moiety, heterocycles containing

Sulfur-containing aromatic heterocycles

Sulfur-containing heterocycle synthesis

Sulfur-containing heterocycles

Sulfur-containing heterocycles photochemistry

Sulfur-containing heterocyclic

Sulfur-containing heterocyclic compounds with antioxidative activity

Sulfur-containing heterocyclic ring

Sulfur-containing heterocyclic systems

Sulfur-containing six-membered heterocycles

Sulphur-containing heterocycles

Synthesis of 2-Pyridone Containing Heterocycles

Synthesis of Heterocyclic Compounds Containing a Carbonyl Moiety by Radical Carbonylations

Synthesis of Nitrogen-Containing Heterocyclic (Z)-1,3-Dienes

Synthesis of Quinoxalines from Various Fused Nitrogen-Containing Heterocycles Without a Pyrazine Fragment

Tellurium-Containing Heterocycles with N-Bridged Atoms

Tellurium-Nitrogen-Containing Heterocycles

Tellurium-containing heterocycles with two

Tellurium-containing heterocycles with two heteroatoms

Thiazoles and Related Sulfur-Nitrogen-Containing Heterocycles

Triosmium complexes from sulfur-containing heterocycles

Unsaturated nitrogen heterocyclic compounds containing carbonyl groups

Unsaturated nitrogen heterocyclic compounds containing carbonyl groups, chemistry

Urea derivatives containing a heterocyclic group

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