Photoaddition anthracene

Flegel, M. Lukeman, M. Huck, L. Wan, P. Photoaddition of water and alcohols to the anthracene moiety of 9-(2 -hydroxyphenyl)anthracene via formal excited state intramolecular proton transfer. J. Am. Chem. Soc. 2004, 126, 7890-7897. 

A number of other aromatic compounds have been observed to undergo photoaddition to anthracene to yield products similar in structure to the anthracene dimer ... 

In the case of the photoaddition of anthracene derivatives and tetracene, the cross-dimer is the major product isolated in all cases even when anthracene itself is used. 

Recently the photoaddition of anthracene and simple dienes was discovered ... 

An example of the equivalent (photoaddition) reaction following hetero-molecular photoassociation is provided by the photochemical addition of maleic anhydride to anthracene." Livingston and coworkers100 have shown that the anthracene triplet state is not involved in this reaction and that, in terms of Eq. (47) in the appropriate form, q%. = 0.03. However, if the excited complex XMQ formed directly by light absorption in the charge-transfer band is the reactive intermediate, this produces the adduct with a computed efficiency of 347 . 

Additions to Aromatic Hydrocarbons. A variety of photochemical additions to aromatic hydrocarbons have been reported. Benzene and its derivatives add to maleic anhydride74-76 as well as to simple olefins,77-80 isoprene,81 acetylene derivatives,79,82 and alcohols.83 The mechanism of the maleic anhydride-benzene reaction is discussed in Section IV. A.4. Naphthalene forms a photoadduct with dimethyl acetylenedicarboxylate62 and with acrylonitrile8211 while anthracene behaves similarly with maleic anhydride84 and with 1,2-benzanthracene.85 The photoaddition of several aromatic amines to anthracene has been reported to proceed via a charge transfer complex86,87 in fact, the majority of these addition reactions may proceed in this manner. 

The reactive state of anthracene involved in the photoaddition reaction between anthracene and CC14 has been a point of controversy. An attempt has been made to establish the reactive state by populating anthracene triplet state by triplet-triplet energy transfer process ... 

A series of intramolecular photoadditions of one anthracene nucleus to another resulting in the formation of heterocycles have been reported in certain dianthryl derivatives.273 9-Anthryl-9-anthramide (262), on irradiation in benzene yields the /3-lactam (263) the corresponding carbonate and azo compound undergo analogous cyclizations. 

Photoinduced electron transfer between amines and aromatic hydrocarbons occurs to generate radical cations of amines and radical anions of aromatic hydrocarbons. Pac and Sakurai reported the photoaddition of N,N-dimethylaniline to anthracene via photoinduced electron transfer [60]. In benzene, the 4n + 4n) photocyclodimer of anthracene is produced as a sole isolable product, although an emission due to the exciplex formed from anthracene and JV,N-dimethylaniline is observed. In acetonitrile, the addition of dimethylaniline to anthracene occurs via their radical ions to give 9,10- dihydro-9-(4 -dimethylaminophenyl)anthracene as the major product. However, the photoamination on anthracene takes place even in benzene when iV-methylani-line is used as an electron donor. Sugimoto and his coworkers reported the intramolecular photoaddition of anilines to aromatic hydrocarbons to give cyclic amino compounds (Scheme 16) [61-63]. 

Many examples exist of the reaction of anthracenes with alkenes and dienes to give products resulting from addition across the 9,10-positions of the anthracene ring. Yang has used this reaction to generate the (4-I-41 adducts (129) which are then converted to the novel para, para linked species (130). These comjpounds are chemiluminescent on thermolysis and yield benzene and, in the case of R=H, singlet excited anthroic acid. The (4+21 photoaddition of... 

The anthracenes (188), which have a 3,5-dialkoxybenzyloxymethyl substituent on the 9-position, undergo quantitative (4jt + 4ji) intramolecular photocycloaddition to yield (189). " The process is thermally reversible, and (189) is readily converted to the diketone (190) on treatment with acid. In the presence of acid, the linked naphthyl and resorcinyl moieties in (191) undergo (2ji -I- 2jt) photoaddition with 300 nm radiation to give the tetrahydrofuran derivatives (192) by the route outlined in Scheme 3." The reaction also occurs in the absence of acid for (191) with R = -0-(CH2)2-0Me, but the quantum efficiency is reduced by 35-fold. The products (192) are labile under 254 nm radiation and undergo a novel photoextrusion of acetaldehyde to yield (193) by the pathway... 

The photochemical Diels-Alder reactions of anthracene with fumarodinitrile and 1,4-benzoquinone have been studied in chloroform solution. Not surprisingly, the addition occurs in competition with dimerization of the arene and proceeds by way of electron transfer from anthracene to the dienophiles. The radical ion pair has been detected by transient absorption spectroscopy, and the resulting diradical precursor of adduct formation from the quinone was observed by ESR at 77 K. 2,7-Dibromotropone is reported to undergo (871+471) photoaddition to 9,10-dicyanoanthracene in benzene-methanol (9 1), giving (25) as the primary adduct which is then proposed to react with methanol and water (solvent contaminant) to yield the final product (26). In contrast, 2-bromotropone and the anthracene in CH2CI2 solution afford the substitution products (27) (62%) and (28) (25%). 

We previously mentioned that excitation localization indices L point to photoactive sites in excited molecule, and as such they can serve as suitable photochemical indices. For instance, anthracene and tetracene undergo photoaddition and photooxidation primarily at the peripheral atoms of central rings, and the diagrams in Table 14.1 agree with this fact. In peri-condensed PAHs, such as pyrene and... 

Other aromatic compounds like naphthalene, its derivatives, anthracene, its derivatives and other compounds shows photoaddition reactions. The photoaddition reaction may be between same compound or different compounds. 

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