Alkynes tetralines

Indan (265, n = 3) and tetralin (265, n = 4) derivatives are obtained from 1,6-heptadiyne or 1,7-octadiyne with simple alkynes in the presence of CpCo(CO)2, and although the yields are not high (14-50%) the products are easily obtained pure by column chromatography""". The synthetic applications of these cyclizations have been reviewed recently""". ... 

The 2-pyrone 116 (Scheme 33), containing the weakly electron-donating carbamate group at C3, has been reported to undergo cycloadditions with alkynes in refluxing decalin or tetralin, providing aniline derivatives 118 upon elimination of CO2 and aromatization... 

The radicals formed by oxidation of 1,3-dicarbonyl compounds will add to electron-rich naphthalenes (eq 11). Tetralins and dihydronaphthalenes can be formed by oxidation of diethyl a-benzylmalonate in the presence of an alkene or alkyne (eq 12). 20-22... 

A synthetically important catalytic mixed cyclotrimerization has been developed recently by Vollhardt using CpCo(CO)2 (Vollhardt, 1977). By combining diynes with bis(trimethylsilyl)acetylene, an alkyne incapable of self-condensation, bicyclic aromatics, including tetralins, indanes, and ben-zocyclobutenes, are readily obtained (Hillard and Vollhardt, 1975). Anthra-quinones have also been prepared from diketodiynes (Hillard and Vollhardt,... 

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