Cyclodecadienes transannular cyclization

The reaction of A -nitrosodimethylamine with (f.ZH.S-cyclodecadiene gave a mixture of two diastereomeric amino nitrates arising from transannular cyclization of the intermediate carbon radical102. The corresponding alcohols 1 and 2 are obtained by reduction of the crude mixture with lithium aluminum hydride. 

Transannular cyclizations of cyclodecadiene monoepoxides have been studied in exhaustive detail, particularly amongst natural germacranolides, because of their relevance to biogenetic models for the synthesis of eudesmane- and guaiane-type sesquiterpenes. " A full discussion of this topic is beyond the scope of this chapter, but the examples collected in equations (54-64) provide the reader with an in-... 

Stereoselective transannular cyclizations to hydroazulene systems are also described. These reactions are initiated by ionization of cyclodecenol to form an allylic cation or by oxirane ring opening in cyclodecadiene monoepoxides. 

On cyclizing (E,Z) or (Z.Z)-cyclodecadienes a mixture of trans- and ra-decalins is observed. An explanation for this fact could be the existence of two favored conformations, both of which undergo the transannular reaction36. 

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