Heterocyclic derivatives synthesis

Homophthalic anhydrides in synthesis of heteroeycies 84KGS1587. Metallation as key step in heterocyclic synthesis 83S957. a-Methylamino acids—heterocyclic derivatives, synthesis of 85MI21. Polysubstituted heteroeycies in syntheses of bi- and polycyclic systems ... 

Whereas the fulvalenes 1-6 are relatively unstable hydrocarbons and therefore largely of theoretical interest, their heteroatom analogs demand considerable attention in synthetic chemistry and material sciences. Tlie general principle of heterocyclic chemistry to relate heterocyclic compounds to carbocyclic ones was the driving force for the synthesis and their application to heteroful-valenes. Numerous heterocyclic derivatives iso-rr-electronic with, for example, heptafulvalene 3 were accessible in which pairs of carbon atoms linked by double bonds were replaced by heteroatoms capable of contributing two tt-electrons. By this principle, the well-known tetrathiafulvalene and its derivatives have been synthesized successfully (Scheme 2). 

Heterocycles in synthesis of herbicide glyphosate heterocyclic derivatives and analogs of glyphosate 97PHC17. 

Jones G (1996) Pyridines and their benzo derivatives synthesis. In McKillop A (ed) Comprehensive heterocyclic chemistry 11. Pergamon Press, Oxford, p 167/Chap. 5.05... 

Table 2 A comparison between conventional heating and microwave-assisted synthesis in an intramolecular Heck coupling to heterocyclic derivatives of 2-quinolones 20 and 21. Note the high selectivity in (b), where two possibilities exist to fuse a six-membered ring...

The synthesis of new heterocyclic derivatives under conservation of a preformed cyclic structure is not only of particular importance for the synthesis of ionic 1,3,2-diazaphosphole or NHP derivatives but has also been widely apphed to prepare neutral species with reactive functional substituents. The reactions in question can be formally classified as 1,2-addition or elimination reactions involving mutual interconversion between 1,3,2-diazaphospholes and NHP, and substitution processes. We will look at the latter in a rather general way and include, beside genuine group replacement processes, transformations that involve merely abstraction of a substituent and allow one to access cationic or anionic heterocycle derivatives from neutral precursors. 

Heterocyclic derivatives such as 59 provide a convenient route to the synthesis of many cyclic germanium compounds87. For instance, photolysis of 59 in the presence of alkynes 60 or 61, or allenes 62, produces the unsaturated heterocyclic compounds 63 or 64, respectively. 

The aforementioned section described the synthesis of a wide range of biologically important heterocyclic derivatives of combretastatin. The next part of this chapter will focus on the synthesis of heterocyclic chalcone derivatives. 

Considerable difficulties are often experienced in the preparation of basic dyes from quaternised heterocyclic diazo components. An alternative technique is to use an oxidative coupling procedure, in which a mixture of a hydrazone and a coupling component is treated with a mild oxidising agent, such as a hexacyanoferrate(III) [102] an azo compound is then produced as shown in Scheme 4.36 for the synthesis of Cl Basic Red 30 (4.100) [103]. Quaternisation of heterocyclic derivatives can lead to the formation of mixtures of isomers, as in the case of Cl Basic Red 22 (4.101). As well as the 2,4-dimethyl derivative shown, the product contains about 15% of the 1,4-dimethyl isomer [104]. 

Synthesis of Functionalized Indole- and Benzo-Fused Heterocyclic Derivatives through Anionic Benzyne Cyclization... 

Abstract The basic principles of the oxidative carbonylation reaction together with its synthetic applications are reviewed. In the first section, an overview of oxidative carbonylation is presented, and the general mechanisms followed by different substrates (alkenes, dienes, allenes, alkynes, ketones, ketenes, aromatic hydrocarbons, aliphatic hydrocarbons, alcohols, phenols, amines) leading to a variety of carbonyl compounds are discussed. The second section is focused on processes catalyzed by Pdl2-based systems, and on their ability to promote different kind of oxidative carbonylations under mild conditions to afford important carbonyl derivatives with high selectivity and efficiency. In particular, the recent developments towards the one-step synthesis of new heterocyclic derivatives are described. 

Ager, D. J. Prakash, L Schaad, D. R. (1996) 1,2-Amino Alcohols and Their Heterocyclic Derivatives as Chiral Auxiliaries in Asymmetric Synthesis., Chem. Rev., 96, 835-876... 

Major advancements in the chemistry of pyrazoles, imidazoles, triazoles, tetrazoles, and related fused heterocyclic derivatives appeared in 1999. Solid-phase combinatorial chemistry of benzimidazoles and tiiazoles has been particularly active. Synthetic routes to all areas continue to be pursued vigorously with improvements and applications. In medicinal chemistry, synthesis and structure-activity relationship (SAR) studies utilizing these core structures have been exploited heavily. The physical organic chemistry of pyrazoles and imidazoles continue. 

Studies on the Chemistry of Thienoannulated 0,N- and S,N-Containing Heterocycles. 1. Nucleophilic Substitution Reactions on Chlorinated Thiophene Derivatives as a Basis for the Synthesis of Thienoannulated 0,N- and S,N-Heterocycles, Puschmann, I. Erker, T. Heterocycles 1993,36,1323. See also Studies on the Chemistry of Thienoanellated 0,N- and S,N-Containing Heterocycles. II. Synthesis on Thieno-Dilthiazem Analogs, Puschmann, 1. Erker, T. Heterocycles 1995, 41, 709. 

Research in the Department of Chemistry of the School of Pharmacy of the University of Bari Nucleophilic Reactivity of Aromatic Derivatives, and Synthesis and Reactivity of Heterocyclic Derivatives P. E. Todesco, Corsi Semin. Chim., 1968, 50-53. Nucleophilic Heteroaromatic Substitution G. Illuminati, Adv. Heterocyclic Chem., 1964, 3, 285-371. 

Extraction, determination of structures, partial or total synthesis of the simple or complex heterocyclic derivatives constituting the natural benzofuran derivatives of vegetable origin. 

N. J. Leonard and K. L. Carraway, 5-Amino-5-deoxyribose derivatives. Synthesis and use in the preparation of reversed" nucleosides, J. Heterocycl. Chem. 3 485 (1966). 

In view of the widespread use of tertiary phosphines in coordination chemistry, it is somewhat surprising that phosphorus-containing macrocycles have not evoked more interest. In part this is undoubtedly due to experimental difficulties. The synthesis of P macrocycles is doubly difficult, since the usual difficulties and hazards of phosphorus(III) chemistry are compounded by the complexities and low yields of multistage heterocyclic macrocyclic syntheses. Because of these difficulties, the development of synthetic methods has been slow. Mann s survey73 of the heterocyclic derivatives of P, As, Sb and Bi did not mention phosphorus macrocycles and recent textbooks74,75 give them only cursory mention. 

Nitrogen based heterocycles are present in an array natural products, thousands of which have been mentioned in clinical or preclinical studies.1 Thus, the synthesis of piperidine-2 and pyrrolidine-3 derivatives have attracted much attention from the modem day organic chemists. Of particular interest are strategies that lead to chiral heterocyclic derivatives.4... 

The most efficient photosubstitution reaction, with many applications in synthesis, is the photobromination method developed by FERRIER s group [24]. The substitution of H-5 is regioselective and stereoselective for pentopyranosides [25], hexo-pyranosides [26], 1-6 anhydrosugars [27], uronic acids [24, 28] heterocyclic derivatives from deoxyinosones [29], nucleosides [30, 31], etc.. . using bromine or N-bromo-succinimide in carbon tetracloride under irradiation. 

The first chapter is devoted to the formation and subsequent modification of three-membered heterocycles—aziridines. Synthesis and properties of aziridinyl ketones, bi- and tricyclic aziridine derivatives, cycloaddition and photochemical reactions are described. The second chapter deals with... 

Homolytic substitution of heteroaromatic compounds, 16, 123 Hydantoins, chemistry of, 38, 177 Hydrogen cyanide derivatives, synthesis of heterocycles from, 41, 1 Hydrogen exchange base-catalyzed, 16, 1 one-step (labeling) methods, 15, 137 Hydrogenated porphyrin derivatives hydroporphyrins, 43, 73 Hydroxamic acids, cyclic, 10, 199 1 -Hydroxyindoles, 1 -hydroxytryptophans, and 1-hydroxytryptamines,... 

Among the heterocyclic derivatives, carbazole ring has emerged as a vital building block in the synthesis of many useful optoelectronic materials.93-96... 

From Allenic Phosphorus Derivatives to Heterocyclic Compounds Synthesis of a... 

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