Anthracene, synthesis

The discovery that benzyne (Scheme 30) adds to acridizinium ion to produce an azoniatrip-tycene (34) which, on reduction with sodium borohydride followed by hydrolysis, affords anthracene, offers a new route to the synthesis of related hydrocarbons (71JOC3002). This, the Fields anthracene synthesis, has already found application in the preparation of 1,4,5,8,9-pentamethylanthracene (75TL4639). 

Rigaudy, J., Scribe, P., Breliere, C., Photochemical Transformations of Endoperoxides Derived from Polycyclic Aromatic Hydrocarbons. 1. Case of the Photooxide of 9,10 Diphenyl Anthracene Synthesis and Properties of the Diepoxide Isomer, Tetrahedron 1981, 37, 2585 2593. 

Anthracene synthesis. Anthracene (1) can be obtained in one step when bromobenzene is refluxed in THF in the presence of this base. The yield is... 

Dimethyibenz a anthracene synthesis. The key step in a new synthesis of this system is the reaction of 1 with methyl 2-naphthyl ketone (2) to give, after acid hydrolysis, the phthalide 3 in 62% yield. This product is reduced to 4 with zinc in alkali. Remaining steps involve introduction of the 12-methyl group and cyclization. Similarly, methyl 1-naphthyl ketone affords lO-methoxy-7,12-dimethylbenz[a]anthracene in 277o overall yield. 

Kammermeier S, Jones PG, Merges R (1996) Ring-expanding metathesis of tetradehydro-anthracene—synthesis and structure of a tubelike, fully conjugated hydrocarbon. Angew Chem Int Ed 35(22) 2669-2671... 

Scheme 3.32 Silver(I)-catalyzed substituted anthracene synthesis.

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