Benz a anthracene

Benz[a]anthracene-7,12-dione, available from Eastman Organic Chemicals, was used without further purification. 

Alumina sufficient to adsorb the complete solution is added, then the solvent is removed under vacuum. While benz[a]anthracene, np 157-158°C, sufficiently pure for most purposes, can be obtained by crystallization of the crude product from ethanol-water, filtration" through alumina removes residual, colored impurities, affording a pure, white product. 

Pure benz[a]anthracene has been reported to melt at 158-159°, 160°, and 167°C. The submitters report a mp of 164-164.5°C. The submitters conducted this preparation on a scale five times larger and reported yields up to 954. 

The synthetic procedure described is based on that reported earlier for the synthesis on a smaller scale of anthracene, benz[a]anthracene, chrysene, dibenz[a,c]anthracene, and phenanthrene in excellent yields from the corresponding quinones. Although reduction of quinones with HI and phosphorus was described in the older literature, relatively drastic conditions were employed and mixtures of polyhydrogenated derivatives were the principal products. The relatively milder experimental procedure employed herein appears generally applicable to the reduction of both ortho- and para-quinones directly to the fully aromatic polycyclic arenes. The method is apparently inapplicable to quinones having an olefinic bond, such as o-naphthoquinone, since an analogous reaction of the latter provides a product of undetermined structure (unpublished result). As shown previously, phenols and hydro-quinones, implicated as intermediates in the reduction of quinones by HI, can also be smoothly deoxygenated to fully aromatic polycyclic arenes under conditions similar to those described herein. 

Benz[a]anthracene [56-55-3] M 228.3, m 159-160". Crystd from MeOH, EtOH or benzene (charcoal), then chromatographed on alumina from sodium-dried benzene (twice), using vacuum distn to remove benzene. Final purification was by vacuum sublimation. 

Photoisomerization of benz[a]anthracene 3,4-oxide, triphenylene 1,2-oxide, and benz[a]an-thracene 1,2-oxide yields anthra[2,l-6]oxepin [mp 125-126 C (pentane/Et20)], phen-anthro[10,9-/r]oxepin [mp 109-110°C (hexane/Et20)], and anthra[2,1 -/joxepin [mp 70CC (dec., pentane/Et20)], respectively.12 0... 

RATE COEFFICIENTS FOR REACTION OF BENZ[a]ANTHRACENES WITH CF3COOD... 

Danishefsky et al. succeeded in preparing the benz[a] anthracene core structure 111 of angucycline antibiotics by performing a benzannulation reaction with the cycloalkynone 109 [69]. Deprotonation of the naphthoquinone 110 with DBU yields the desired anthraquinone 111 (Scheme 49). 

Scheme 49 Synthesis of the benz[a] anthracene core structure...

Figure 3 depicts profiles of Total PAH fluxes vs. time (36). The following polycyclic hydrocarbons have been determined by high performance liquid chromatography, variable wavelength absorption detection Naphthalene, acenaphthylene, 7,12-dimethylbenzanthracene, 2-methylnaphtalene, fluorene, acenaphtene, phenanthrene, 2,3-dimethylnaphtalene, anthracene, fluoranthene, 1-methylphenanthrene, pyrene, 2,3-benzofluorene, triphenylene, benz(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, perylene, benzo(e)pyrene, 1,2,3,4-dibenzanthracene, benzo(a)pyrene, and 1,2,5,6-dibenzanthracene. 

Jang M, SR McDow (1997) Products of benz/a/anthracene photodegradation in the presence of known organic constituents of atmospheric aerosols. Environ Sci Technol 31 1046-1053. 

Note Bi, biphenyl Nap, naphthalene Phe, phenanthrene Anth, anthracene Hu, fluoranthene Pyr, pyrene Chr, chrysene BaAnth, benz[a]anthracene BaPyr, benzo[a]pyrene BbFlu, benzo[h]fluoranthene DBaAnth, dibenz[a,/i]anthracene 3-Me-Chol, 3-methylcholanthrene. 

Schneider J,RGrosser,KJayasimhulu,WXue,DWarshawsky(1996)Degradationofpyrene,benz[a]anthracene, and benzo[a]pyrene by Mycobacterium sp. strain RGHll-135, isolated from a former coal gasification site. Appl Environ Microbiol 62 13-19. 

FIGURE 8.14 Pathways for partial degradation of benz[a] anthracene. (From Neilson, A.H. and Allard, A.-S. The Handbook of Environmental Chemistry, Springer, 1998. With permission.)... 

Mahaffey WR, DT Gibson, CE Cerniglia (1988) Bacterial oxidation of chemical carcinogens formation of polycyclic aromatic acids from benz[a]anthracene. Appl Environ Microbiol 54 2415-2423. 

Moody JD, PP Fu, JP Freeman, CE Cemiglia (2003) Regio-and stereoselective metabolism of 7,12,dimethyl-benz[a]anthracene by Mycobacterium vanbaalenii PYR-1. Appl Environ Microbiol 69 3924-3951. 

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