Arene synthesis

F. Sansone, L. Baldini, A. Casnati, and R. Ungaro, Conformationally mobile glucosylthioureidocalix[6]- and calix[8]arenes Synthesis, aggregation and lectin binding, Supramol. Chem., 20 (2008) 161-168. 

One of the most important reactions in arene synthesis is the halogenation of arenes. Conventionally, these reactions are performed directly by bromine or chlorine [7]. However, on the laboratory scale chlorine is not easily manageable and is a toxic gas. Therefore, it is not often used in academic research. For iodinations normally a strong oxidizing agent is required. In halogenations, often unintentional side-chain... 

Rfiu CN)Li2 arene synthesis. Aryl tritlates or nonaflates do not couple with R2CuLi, but they do couple with the mixed eupiates R2Cu(CN)Lii to give alkylarenes in 40-95% yield. Substituents on the aromatic ring have little effect in the reaction. Example ... 

G. M. Whitesides and W. J. Ehmann, 7. Am. Chem. Soc., 1969, 91, 3800 see also G. A. Ville, K. P. C. Vollhardt and M. J. Winter, Organometallics, 1984, 3, 1177 for further studies along these lines, and J. R. Strickler, P. A. Wexler and D. E. Wigley, Organometallics, 1988, 7, 2067 for studies of relevant model systems associated with alkyne trimerizations catalyzed by early transition metals. Note that although cyclobutadiene-like structures are not involved in most alkyne trimerization mechanisms, metal-complexed cyclobutadienes are fairly common side products in alkyne trimerization reactions. As their yields are usually low, their formation does not present practical problems in arene synthesis. 

Frick, W, Schmidt, R R, Convenient synthesis of C- 3-D-glucopyranosyl arenes. Synthesis of 5,7,4 -tri-O-methylvitexin, Liebigs Ann. Chem., 565-570, 1989. 

Cyclizations Involving Fischer Carbene Complexes The Dotz Arene Synthesis... 

The Dotz arene synthesis is an excellent technique for construction of complex, densely functionalized aromatic ring systems. Equations 12.85-12.87 present three examples. 

Megaphones, synthesis of 1250, 1252 Mercaptocalix[4]arenes, synthesis of 1402 [l.l.l.l]Metacyclophane framework 322 [l ]Metacyclophanes 1370 Metalation, directed 677 Metathesis reactions 1432 trarw-3-Methoxy-4-hydroxycinnamic acid, as MALDl matrix 323 Methoxylation 1167... 

Titanium complexes of oxacalix[3]arenes - synthesis and mechanistic studies of their dynamic isomerization, P. D. Hampton, C. E. Daitch, T. M. Alam, Z. Bencze and M. Rosay, Inorg. Chem., 1994, 33, 4750. 

Yoshida. M. Goto, M. Nakanishi, F. Silicon-bridge metacyclophanes as parent compounds of silacalix[/ ]-arenes. Synthesis, structures, and confrmational analysis by semiempirical MO calculations. Organometallics 1999. 18, 1465. 

If triple bonds are implemented in cycloadditions with six-membered cychc dienes, an irreversible release of an alkene moiety claims for another type of arene synthesis. Driven by the search for novel antitumor agents, Danishefsky exploited this strategy during the synthesis of cycloproparadicicol [13]. The dimedone-derived electron-rich diene 22 cycloadds to the activated triple bond of the compound termed ynolide 23 at elevated temperatures, whereupon a concomitant extrusion of isobutene uncovers the aromatic core (Scheme 6.5). The trimethylsilyl (TMS) ether groups get cleaved during chromatography, furnishing the precursor 25 of cycloproparadicicol in 75% yield. 

Stannic chloride Diarylacetic acids from arenes Synthesis with addition of two C-atoms... 

Hojczyk KN, Feng P, Zhan C, Ngai M-Y (2014) Trifluoromethoxylation of arenes synthesis of ortho-trifluoromethoxylated aniline derivatives by OCF3 migration. Angew Chem Int Ed... 

Key words Metallocene calix[4]arenes, synthesis, variable temperature NMR studies, electrochemistry. 

Most arene complexes are hexahapto, and ternary complexes usually have 18 valence electrons. The most known and used ones for their applications in arene synthesis are the arene-metal-tricarbonyls (columns of chromium and manganese), in particular the arene-chromium-tricarbonyl and the arene-manganese-tricarbonyl cations... 

Diversity of Building Blocks and Approaches for Oxacalix[4]arene Synthesis... 

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