Benzo-anellation procedure

The Diels-Alder reaction is the most important method for the construction of six-membered rings. For example it can be used as a step in a benzo-anellation procedure. The experimental procedure is simple, and yields are generally good side reactions play only a minor role. 

The unsaturated substituent in the carbene complex 1 often is aromatic or heteroaromatic, but can also be olefinic. The reaction conditions of the Dotz procedure are mild various functional groups are tolerated. Yields are often high. The use of chromium hexacarbonyl is disadvantageous, since this compound is considered to be carcinogenic however to date it cannot be replaced by a less toxic compound. Of particular interest is the benzo-anellation procedure for the synthesis of anthra-cyclinones, which are potentially cytostatic agents. ... 

Benziodoxol-3( 1 ff)-one, l,l,l-tris(acetyloxy)-1,1-dihydro- (Dess-Martin periodinane, DMP) oxidation of alcohols, 134, 328-329 Benzo-anellation procedure, 337 Benzocyclobutenes. See Bicyclo[4.2.0]octa-1,3,5-trienes... 

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See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

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