Acylation naphthalene

Cerveny, L., Mikulcova, K., and Cejka, J. 2002. Shape-selective synthesis of 2-acetylnaphthalene via naphthalene acylation with acetic anhydride over large pore zeolites. Appl. Catal. A Gen. 223 65-72. 

When the cyclic component is benzene or naphthalene, the -ic acid or -oic acid of the acid corresponding to the acyl group is changed to -ophenone or -onaphthone, respectively. For example, C5H5—CO—CH2CH2CH3 can be named either butyrophenone (or butanophenone) or phenyl propyl ketone. 

A further consequence of association of acylating agents with basic compounds is an increase in the bulk of the reagent, and greater resistance to attack at the more stericaHy hindered positions of aromatic compounds. Thus acylation of chrysene and phenanthrene in nitrobenzene or in carbon disulfide occurs to a considerable extent in an outer ring, whereas acylation of naphthalene leads to extensive reaction at the less reactive but stericaky less hindered 2-position. 

Anthraquinone dyes are derived from several key compounds called dye intermediates, and the methods for preparing these key intermediates can be divided into two types (/) introduction of substituent(s) onto the anthraquinone nucleus, and (2) synthesis of an anthraquinone nucleus having the desired substituents, starting from benzene or naphthalene derivatives (nucleus synthesis). The principal reactions ate nitration and sulfonation, which are very important ia preparing a-substituted anthraquiaones by electrophilic substitution. Nucleus synthesis is important for the production of P-substituted anthraquiaones such as 2-methylanthraquiQone and 2-chloroanthraquiaone. Friedel-Crafts acylation usiag aluminum chloride is appHed for this purpose. Synthesis of quinizatia (1,4-dihydroxyanthraquiQone) is also important. 

For the acylation of naphthalene, the ionic liquid gives the highest reported selectivity for the 1-position [95]. The acetylation of anthracene at 0 °C was found to be a reversible reaction. The initial product of the reaction between acetyl chloride (1.1 equivalents) and anthracene is 9-acetylanthracene, formed in 70 % yield in less than 5 minutes. The 9-acetylanthracene was then found to undergo diacetylation reactions, giving the 1,5- and 1,8-diacetylanthracenes and anthracene after 24 hours (Scheme 5.1-64). 

Resolution (enantiomers), 307-309 Resonance, 43-47 acetate ion and, 43 acetone anion and. 45 acyl cations and, 558 allylic carbocations and, 488-489 allylic radical and, 341 arylamines and, 924 benzene and, 44. 521 benzylic carbocation and, 377 benzylic radical and, 578 carbonate ion and. 47 carboxylate ions and, 756-757 enolate ions and, 850 naphthalene and, 532 pentadienyl radical and. 48 phenoxide ions and, 605-606 Resonance effect, 562 Resonance forms, 43... 

A convenient route to highly enantiomerically enriched a-alkoxy tributylslannanes 17 involves the enanlioselective reduction of acyl stannanes 16 with chiral reducing agents10. Thus reaction of acyl stannanes with lithium aluminum hydride, chirally modified by (S)-l,l -bi-naphthalene-2,2 -diol, followed by protection of the hydroxy group, lead to the desired a-alkoxy stannanes 17 in optical purities as high as 98 % ee. 

The greater steric hindrance to acetylation was also shown by a comparison of the rate of (103At2) of acetylation of toluene (0.763), ethylbenzene (0.660), i-propylbenzene (0.606) and f-butylbenzene (0.462) with those (determined by the competition method) for benzoylation both sets of data (Table 112) were obtained with dichloroethane as solvent at 25 °C, all reagent concentrations being 0.1 A/421. Relative rates of acylation other aromatics under the same conditions have also been obtained and are given in Table 113422. The different steric requirements for acetylation and benzoylation are further shown by the following respective relative rates for acylation of naphthalene derivatives in chloroform at 0 °C naphthalene (1 position) 1.00,1.00, (2 position) 0.31,0.04 2,3-dimethylnaphthalene (1 position) 1.59, 172, (5 position) 7.14, 38.2, (6 position) 3.68, 7.7422a. 

Another recent patent (22) and related patent application (31) cover incorporation and use of many active metals into Si-TUD-1. Some active materials were incorporated simultaneously (e.g., NiW, NiMo, and Ga/Zn/Sn). The various catalysts have been used for many organic reactions [TUD-1 variants are shown in brackets] Alkylation of naphthalene with 1-hexadecene [Al-Si] Friedel-Crafts benzylation of benzene [Fe-Si, Ga-Si, Sn-Si and Ti-Si, see apphcation 2 above] oligomerization of 1-decene [Al-Si] selective oxidation of ethylbenzene to acetophenone [Cr-Si, Mo-Si] and selective oxidation of cyclohexanol to cyclohexanone [Mo-Si], A dehydrogenation process (32) has been described using an immobilized pincer catalyst on a TUD-1 substrate. Previously these catalysts were homogeneous, which often caused problems in separation and recycle. Several other reactions were described, including acylation, hydrogenation, and ammoxidation. 

The important bluish mixing component 11.22 for whitening polyester is made by Friedel-Crafts acylation of pyrene (Scheme 11.17). This tetracyclic hydrocarbon is not unlike anthracene in its susceptibility to substitution reactions. The most stable bond arrangement in pyrene appears to be that shown as form 11.47a, which contains three benzenoid (b) rings. Canonical form 11.47b, containing only two such rings, contributes to a lesser extent (Scheme 11.18). In all monosubstitutions, pyrene is attacked initially at the 3-position, corresponding to the a-positions in anthracene or naphthalene. 

Comparative attempts at graphite-supported acylation of anisole, toluene, and naphthalene using classical heating afforded interesting results [66]. With nonvolatile reactants the yields were almost identical with those obtained under the action of MW. In contrast, if at least one reactant was volatile (MeCOCl, PrCOCl) or sublim-... 

It is not out of the question that a complex of the general character of XLIII should function as an acylating agent itself. It will be recalled that the position of acylation of naphthalene is often determined by the... 

Such activity enhancement can be ascribed to planarity of the naphthalene nucleus and its disposition for n-n stacking between the DNA base pairs. There is no literature precedence for involvement of naphthalene in such processes unless it is % electron deficient.211,212 However, our results suggest that both alkylated and acylated naphthalenes are intercalators with bacterial DNA. 

As described above, when CuCl is regenerated in the reaction, the process can be catalytic in copper. In other cases, a stoichiometric amount (2 equiv.) of CuCl is used. Although CuCN shows similar reactivity, CuBr and Cul are not so effective as compared to CuCl. Allylation benzene, naphthalene, and anthracene formation, as well as acylation are representative examples, which are described below. 

Compounds 1 and 2 were identified by FTIR and 13C-NMR. The 13C proton decoupled spectra for 1 and 2 are dominated by signals ranging from 62 to 195 ppm. The 13C chemical shift assignments were made based on comparisons with 4,4 -(hexafluoroisopropylidene)diphenol and from calculations based on substituted benzenes and naphthalenes.15 The 13C-NMR spectrum clearly showed that the Friedel-Crafts acylation of 1 by 4-fluorobenzoyl chloride yielded the 1,4-addition product exclusively. The 13C chemical shifts for 2 are listed in Table 8.1. The key structural features in the FTIR spectrum of2 include the following absorptions aromatic C-H, 3074 cnr1, ketone C=0, 1658 cm-1, aromatic ether Ar—0—Ar, 1245 cm-1, and C—F, 1175 cm-1. 

Anthraquinone itself is traditionally available from the anthracene of coal tar by oxidation, often with chromic acid or nitric acid a more modern alternative method is that of air oxidation using vanadium(V) oxide as catalyst. Anthraquinone is also produced in the reaction of benzene with benzene-1,2-dicarboxylic anhydride (6.4 phthalic anhydride) using a Lewis acid catalyst, typically aluminium chloride. This Friedel-Crafts acylation gives o-benzoylbenzoic acid (6.5) which undergoes cyclodehydration when heated in concentrated sulphuric acid (Scheme 6.2). Phthalic anhydride is readily available from naphthalene or from 1,2-dimethylbenzene (o-xylene) by catalytic air oxidation. 

Primary and secondary amines are acylated by acid chlorides and anhydrides, in particular also by the chloride of benzene sulphonic add (p. 192). The preparation of acetanilide has already been described (pp. 125, 128). The acetyl- and benzoyl-derivatives of all the simpler primary amines of the benzene and naphthalene series are known, so that these derivatives can always serve for purposes of identification. 

Amino-substituted naphthoquinones and heterocyclic variants have been disclosed in the patent literature as 5-LO inhibitors. Compounds represented by (80) (X = C, N) from Lilly inhibited SRS-A release from sensitized guinea-pig lung tissue [218]. Similar compounds such as (81) (R = carboxylic ester, acyl, or aryl) and related naphthalene derivatives, from American Cyanamid, gave good inhibition in guinea-pig ISN (at 10 //g/ml) and in passive cutaneous anaphylaxis in mice (25-60 /zM i.p.) [219,220]. 

With one exception, naphthalen-l,4-imines with a double bond between C-2 and C-3 are not known to dissociate thermally by either possible retro-Diels-Alder pathway (the reverse of reactions described in Section III, A, 1 and 2), and the enthalpy requirements for the formation of a benzyne or an acylic acetylene are doubtless unfavorable. However, the mass spectra of compounds 93-99 reveal one important fragmentation of the molecular ions to be loss of dimethyl acetylene-dicarboxylate, and another fragmentation pathway involves the formation of nitrilium ions MeC=NR and PhC=NR from 93-95 and 96-99, respectively. ... 

Zinc was effectively activated from zinc chloride using lithium and a catalytic amount (10%) of naphthalene in order to prepare secondary or tertiary alkylzinc bromides 517 (starting from the corresponding aUcyl bromides 516). These reagents react with acyl chlorides or a,/3-unsaturated ketones to give the expected ketones 15 and 518 (Scheme 143). 

Finally, starting with suitable Af-chlorohydroxamic esters, efficient cyclization of Af-acyl-A-alkoxynitrenium ions onto the naphthalene skeleton, giving 71-73, has been reported using Zn(OAc)2 in nitromethane. ... 

---