Acenaphthenes synthesis

The Balz-Schiemann synthesis can be applied not only to substituted anilines but also to aminobiphcnyls1,131 or amino-substituted fused polyaromatic compounds, such as naphthalene,1114,119,129 anthracene,136 phenanthrene,1135 acenaphthene,133 fluorene,1,131,134 benzanthracene,130 136 pyrene,136 chrysene,136 fluoranthene,131 fluorenone,1,131 anthra-quinone,1,137,139,140 benzanthrone,1,117,118 phenanthraquinone,138 or xanthone.132 Fluorinated pyridines,1,141"146 methylpyridincs,126,147 149 pyridinecarboxylic acids,150 quinolines,1,151 isoquinolines,152 quinazolone,1 thiazoles,153,154 isothiazoles,156 benzothiazoles,157 thiadiazoles,155 and thiophenes154 can also be obtained from the corresponding aminated heterocycles. Modified Balz-Schiemann methods are recommended for amino nitrogen-containing heterocycles, the diazonium salts of which are rather water-soluble and unstable (a violent explosion was reported for pyridine-3-diazonium tetrafluoroborate).159 These new techniques have also been specially adapted for pyrazol-, imidazol-, or triazolamines which fail to react under classical conditions.158... 

Of numerous chloral condensations with aromatic hydrocarbons the most interesting for the synthesis of condensation monomers are the reactions with benzene [3], toluene [4], acenaphthene [5], phenol [6], anisol [7], acetanilide [8] and halobenzenes like chlorobenzene [9] and fluorobenzene [10]. In general terms, these reactions proceed according to Scheme 2.2 and give the desired 1,1,1-trichloro-... 

Substituted naphthalenes (acenaphthene, 2-methylnaphthalene) are also formylated by N,N-dialkylforinainides, but in low (20, 26%) yields. Generally speaking, several other methods of formylation and acylation exist in the organic synthesis repertoire. Nevertheless, the procedure described here is useful, for it uses inexpensive starting materials. 

The naphthalimide ring system has the drawback of low effectiveness, which is mainly attributable to the low molar extinction coefficient. The industrial synthesis of alkoxynaphthalimides begins with acenaphthene. Chlorination and subsequent oxidation with dichromate give the corresponding naphthalic acids [116], which are converted to the anhydrides on drying. Mild reaction with methyla-mine, followed by reaction with sodium methoxide or sodium ethoxide, gives, e.g., 64 or 65. 

Chan WK, Hui CS, Man KYK, et al. Synthesis and photosensitizing properties of conjugated polymers that contain chlorotricarbonyl bis(phenylimino)acenaphthene rhenium(I) complexes. Coord Chem Rev 2005 249 1351-9. 

Preformed di-Grignard reagent 126 was utilized for the synthesis of 1-sila-acenaphthene 127 in 10% yield [Eq. (55) 102]. However, a yield of 71% of 127 was realized when 8-bromo-l-chloromethylnaphthalene and dimethyldichlorosilane were reacted in the presence of magnesium. 

Khalaf and coworkershave described a facile synthesis of substituted acenaphthenes (equation 108), and Sharma et al. have reported a synthesis of the precursor for 8-methylbenzo[/]fluoranthene using the cycloalkylation of an arylalkylcarbinol precursor (equation 109). 

Jellimann. C.. Mathe-Allainmat. M.. Andrieux, J., Kloubert, S., Boutin, J.A., Nicolas, J.-P., Bennejean, C.. Delagrange, P., and Langlois. M., Synthesis of phenalene and acenaphthene derivatives as new conformationally restricted ligands for melatonin receptors, J. Med. Chem., 43, 4051, 2000. 

Our expert system is the only predictive software available based on the LSER model. This system also represents the first total codification of the rules and fragment contribution values for synthesis of the four parameter values. Previous publications have either listed partial guidelines for specific classes (27. 28) or have alluded to them (7. 13-17. 27-41). Table III demonstrates the predictive ability of the software for both the LSER parameters and contaminant toxicity. The LSER parameter values are composed from a sum of the contributions from each of the fragments, and the predicted values are generally close to the values composed by hand. For some compounds (such as acenaphthene), the values for 7T, 0, and a may not be accurately represented by a simple sum of fragment variable... 

Figure 2.29 shows the synthesis of 44 from acenaphthene.94 Suzuki-Miyaura coupling of 3-bromoacenaphthene (A) with 4-methoxyphenylboronic acid (B) was the key step to give C in 86% yield. 

The method has been extended to the synthesis of acenaphthylene (8) and acenaphthene (9) as shown.4 The scheme has also been used for six- and seven-... 

Acenaphthene(tricarbonyl)manganese(I) tetrafluoroborate11 is a light yellow solid (mp 130°C decomp.) and is best kept under inert atmosphere to avoid contact with moisture, with which it reacts to liberate the coordinated acenaphthene. Similarly, it reacts rapidly with nucleophilic solvents such as acetonitrile and DMSO but is highly soluble and stable in CH2CI2. It is insoluble in ether and aromatic or aliphatic hydrocarbons. The acenaphthene complex [Mn(t 6-Ci2Hio)(CO)3]BF4 is the MTT reagent of choice in terms of cost, ease of synthesis, and shelf life. 

Removing hydrogen atoms from adjacent carbon atoms, as shown above for stilbene, is generally difficult synthetically. Preliminary work (28) has shown that dianions of acenaphthalene can be prepared by treating acenaphthene with n-BuLi in THF. Unfortunately the technique has limited applicability—for example, similar treatment of 9,10-dihydrophenanthrene does not give dianion formation (28). We have routinely used a modified version of this reaction with the base TMED for years (24, 25)—as above in the synthesis of naphthalene dianion. The dianion of phenanthrene with TMED can also be readily prepared by this reaction ... 

Derivatives of acenaphthene and naphthalic anhydride containing a-dike-tone moieties in the position 4, were applied for preparing bisfnaphthalic anhydrides) having phenylquinoxaline fragments [126-129]. Synthesis of these monomers was carried out according to Scheme 31. 

Reversed-phase EC on chemically bonded Cig (octadecylsilane) stationary phases is by far the most popular liquid chromatographic mode for separation of PAH compounds. Resolution is greatly influenced by the type of synthesis used to prepare the bonded phase. Good resolution can be achieved for the 16 US EPA PAHs on polymeric Cig phases. However, some isomers are unresolved (chrysene and benzo[a] anthracene) or only partially resolved [htmo ght perylene and indeno[l,2,3-cd]pyrene, benzo[ ]fluor-anthene, and benzo[ ]fluoranthene, or fluoranthene and acenaphthene) when monomeric Cig phases are used. 

A new route to pleiadienes involves photoaddition of maleic anhydride derivatives to acenaphthene, oxidative removal of the anhydride groups, and ring-opening of the resulting cyclobutenes (Scheme 18). Schmidt has reported further details of the synthesis of optically active tricarbonyl(cyclobutadiene)iron complexes, the first step involving [2 + 2] addition of 1,2-dichloroethylene to dichloromaleic anhydride. 

Corannulene (1) was synthesized by Lawton and Barth in 1966 [17, 18]. As mentioned by them Within its structural framework is an unusual strain resulting from the geometrical requirement that the bond angles deviate appreciably from the normal values found for benzenoid compounds. Thus, introduction of strain as late as possible is key to their synthetic strategy for the preparation of 1 [19]. Their synthesis started with acenaphthene, and after numerous synthetic steps the key intermediate 4 was obtained (Scheme 1). The diol acid 4 was converted to 5 upon... 

A double coupling of 2-amidoacrylates with 3,3 -diiodobiphenyl constitutes a key step in a short preparation of a biphenomycin B analog. Palladium acetate-catalyzed double coupling reactions of 1,8-diiodonaphthalene with substituted alkenes and alkynes under phase-transfer conditions are useful also for the synthesis of various acenaphthene and acenaphthylene derivatives. ... 

Although many polycyclic hydrocarbons have been identified, only a few are produced and used conunercially. These generally include the simpler compounds, such as naphthalene, acenaphthene, fluorene, and phenan-threne. In the USA, commercial production of petroleum naphthalene was 4.9 X 10 metric tons in 1976, compared with 4.7 and 6.5 X 10 metric tons for 1980 and 1981, respectively (U.S. International Trade Commission, 1960-81). This represented 8-10% of total crude naphthalene production. In Canada, the corresponding consumption was 0.04-0.07 X 10 metric tons for the same time period (Statistics Canada, 1960-80). Naphthalene is used in the manufacture of chemicals such as solvents, lubricants, and dyes. It is also employed as a moth repellent, insecticide, vermicide, anthelmintic, and intestinal antiseptic, and as a feedstock chemical for the synthesis of phthalic anhydride. 

Other polycyclic aromatic hydrocarbons are manufactured in only small amounts. Acenaphthene finds limited use as an intermediate in dyestuff, plastics, and pesticide synthesis. Phenanthrene is also used as an intermediate, whereas 4-ring and 5-ring compounds (chrysene, pyrene, perylene, benzopyrene, dibenzanthracene, and benzanthracene) have few industrial uses. Thus, engine exhaust and other forms of combustion are some of the main sources of PAH in the environment. 

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