| Abstract
| - Aiming at a synthesis of spiro[2.4]hepta-4,6-dienes with a carbon substituent at C-4, we investigatedsolvolysis reactions of the thiatricycle 2, obtained from spiro[2.4]hepta-4,6-diene (1) and thiophosgeneby [4 + 2] cycloaddition. With methanol or ethanol a mixture of the esters 7 and 8 was formed.Desulfurization of the thionoesters 8 gave methyl and ethyl spiro[2.4]hepta-4,6-diene-4-carboxylate(10a,b). The corresponding alcohol (11) was prepared from 10b by LiAlH4 reduction. Ethenetetracarbonitrile combined with the 4-substituted spiro[2.4]hepta-4,6-dienes to give the [4 + 2]cycloadducts 12a−c. Diels−Alder reaction between 11 and 2-chloroacrylonitrile afforded the spiro(bicyclo[2.2.1]hept-5-ene-7,1‘-cyclopropane) derivative 14a that was transformed in three steps torac-10-hydroxycamphor (17). This synthesis of a bornane derivative opens opportunity for variationsand thus may find further applications.
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