Heteroaromatic compounds synthesis

Satoh, M. Miyaura, N. Suzuki, A. 1987. Palladium catalyzed cross-coupling reaction of (1-ethoxy-l-alken-2-yl)boranes with ortho-functionalized iodoarenes. A novel and convenient synthesis of benzo fused heteroaromatic compounds. Synthesis 373-377. 

Sturmer DM (1977) Synthesis and properties - cyanine and related dyes. In Weissberger A, Taylor EC (eds) The chemistry of heteroaromatic compounds, vol 30. Wiley, New York... 

The reactions of heteroaromatic compounds such as furans, pyrroles, and indoles with alkynoates proceed under very mild conditions (in acetic acid or even in neutral solvents such as CH2C12 at room temperature). For example, the reaction of pyrrole with ethyl phenylpropiolate gives the 2-alkenylated pyrrole (Equation (44)).47c This reaction is applied to the direct synthesis of a /3-alkenylpyrrole, the pyrrole fragment of haemin (Equation (45)).47d The present reaction provides a very convenient method for functionalization of arenes and heteroarenes. 

The development of diversification linkers allows introduction of an additional element of diversity. Upon completion of the synthesis sequence, the linker is activated facilitating nucleophilic release of the library members from support In the ideal case, as implemented with the acylsulfonamide linker (Scheme 4a), the activated linker is sufficiently reactive that limiting amounts of nucleophile may be added to provide pure product after resin filtration.181 Diversification linkers have been developed for the preparation of carboxylic acid derivatives (Scheme 4a), amines (Scheme 4b),191 aromatic (Scheme 4c) and even heteroaromatic compounds (Scheme 4d).1101... 

Scheme 4. Use of diversification linkers for the synthesis of (a) amides, (b) amines, (c) aromatic, and (d) heteroaromatic compounds.

Few examples of the preparation of six-membered heteroaromatic compounds using Fischer-type carbene complexes have been reported [224,251,381]. One intriguing pyridine synthesis, reported by de Meijere, is sketched in Figure 2.35. In this sequence a (2-aminovinyl)carbene complex first rearranges to yield a complexed 1 -azadiene, which undergoes intermolecular Diels-Alder reaction with phenylacetylene. Elimination of ethanol from the initially formed adduct leads to the final pyridine. 

The Friedel-Crafts reaction is one of the most important and versatile tools for the formation of carbon-carbon bonds in the synthesis of substituted aromatic and heteroaromatic compounds present in numerous natural products and drugs. Catalytic asymmetric variants using either metal complexes or organic molecules attracted considerable attention over the last few years. 

Subsequently, Kato and Goto have reported the synthesis of 2- and 4-pyridinecarbox-aldoximes from 2- and 4-picoline with potassium amide and amyl nitrite in liquid ammonia at — 33°C, although they failed to obtain either of these oximes when the reaction was carried ont with sodium amide in liquid ammonia at room temperature in a sealed tube. Finally, in 1964, aUcyl-substituted heteroaromatic compounds and allyl-substituted benzenes were oximated in liquid ammonia at —33 °C with sodamide and an alkyl nitrite . 

Alkyl aryl ketones are convenient intermediates for preparing other substituted aromatic and heteroaromatic compounds. Challenger and co-workers " acetylated thieno[2,3-h]thiophene (1) with acetyl chloride and stannic chloride [Eq. (59)]. The 2-acetylthieno[2,3-A]-thiophene obtained by this method was reduced to the 2-ethyl derivative (20) identical with the product of an independent synthesis. ... 

A new class of heteroaromatic compound was introduced by the synthesis of a diphosphathienoquinone (20). It can be reduced to a semiquinone radical anion and dianion at lower potentials than phosphaalkenes. The ESR spectrum indicates that the two P atoms are not equivalent213. 2,4>6-Tricyano- 1,3,5-triazine undergoes dimerization to yield 4,4, 6,6 -tetracyano-2,2 -bitriazine214. 

Heteroalkenes, with iron, 6, 132 Heteroannulation, allylic benzylamines, 10, 156 Heteroarene chromium carbonyls, preparation and characteristics, 5, 260 Heteroarenes borylation, 10, 242 C—H functionalizations, 10, 127 as metal vapor synthesis milestone, 1, 237 with titanium, 4, 246 vanadium complexes, 5, 48 7]6-Heteroarenes, with platinum, 8, 664 Heteroaromatic compounds... 

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,... 

CONTENTS Preface, Brian Halton. Cydopropene-Vinylcar-bene Isomerization and Some Applications in Synthesis, John Warkentin and John McK. R. Wollard. Preparation and Subsequent Reaction Reactions of Halo- and Alkoxyhalocyclopro-panes, Leiv K. Sydnes and Einar Bakstad. The Phenylenes Synthesis, Properties and Reactivity, K.PeterC. Vollhardtand Debra L. Mohler. Cyclobutadienes and Azacyclobutadienes in the Synthesis of Valence Isomers of Six-Membered Aromatic and Heteroaromatic Compounds, Manfred Regitz, Heinrich ... 

Togo and Yokoyama developed a general and efficient method for the synthesis of C-nucleosides employing radical coupling pathways.53 -b Several of these C-nucleosides have been synthesized by ionic pathways but they require many steps and suffer a lack of generality. The thiohydroxamates derived from pentose or 2-tetrahydrofuryl carboxylic acid, Scheme 31, gave the corresponding C-nucleoside derivatives 77 in the presence of an appropriate heteroaromatic compound.53b... 

Collins I, Rapid analogue synthesis of heteroaromatic compounds, J. Chem. Soc., Perkin Trans., 1 2845-2861, 2000. 

The photochemical reactions of naphthoquinones and quinolinediones with 1,1-diarylethenes have led to the synthesis of many new polycyclic aromatic and heteroaromatic compounds. A review has appeared16 in which a number of these results are tabulated. 

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