A. Falcou, C. Boullais
Jul 1, 1998
Citations
0
Influential Citations
4
Citations
Journal
Journal of Labelled Compounds and Radiopharmaceuticals
Abstract
Diethyl [2,3- 13 C 2 ] succinate was prepared by the oxidative dimerization of ethyl lithio [2- 13 C] acetate in the presence of CuBr 2 . Its dienolate was generated with lithium diisopropylamide (LDA) and methylated with CH 3 I to afford diethyl 2-methyl [2,3- 13 C 2 ] succinate which by acid hydrolysis gave the corresponding labelled acid. Treatment of the latter with SOCl 2 provided 2-methyl [2,3- 13 C 2 ] succinic anhydride. This anhydride upon treatment with Et 3 N, ZnCl 2 and trimethylchlorosilane in acetonitrile afforded 2,5-bis (trimethylsilyloxy)-3-methyl [3,4 13 C 2 ] furan which was subjected to a Diels Alder reaction with trichloroethylene giving rise to 2,3-dichloro-5-methyl [5,6- 13 C 2 ] 1,4-benzoquinone which, in turn, was transformed by a known procedure to [2,3- 13 C 2 -2,5-cyclohexadienyl] ubiquinone 3.