C-60-linked carboxylic acid and its derivatives by Diels-Alder cycloaddition of C-60 with a buta-1,3-diene bearing an electron-withdrawing group

Diels-Alder cycloadducts of buta-1,3-dienes having an electron-withdrawing group were utilized for preparation of C-60- linked carboxylic acid familie s; C-60-fused cyclohex-1-enecarboxylic acid was obtained from the cycloaddu ct bearing a tert-butyl eater group by simple acid-catalyzed hydrolysis, an d its aldehyde derivative from the cycloadduct bearing a cyano group by DIB AL reduction. The acid chloride intermediate which was obtained by treatmen t of the acid with oxalyl chloride was converted into amino acid derivative s.