In the search of an electron transfer between π-donors and C60: the bis-linking of tetrathiafulvalene (TTF) to C60

Tetrathiafulvalenes, Oligoacenenes, and Their Buckminsterfullerene Derivatives: The Brick and Mortar of Organic Electronics

“…The Diels−Alder cyclization of fullerene with 4,5-dimethylideneTTF (generated in situ) gave rise to the largest series of TTF−fullerene compounds ( 106 ). Introduced in 1997 by Rovira et al for the synthesis of compound 106d , the reaction has been used recently for preparation of diads 106a , b , d , 106c , 106e − j , and 106h , k , l (Chart ) . The substitution effect in diads 106 is quite predictable: the only known electron-donating substituent (in TTF nucleus), the methyl group ( 106b , E g = 1.03 eV), decreased the oxidation potential of the donor, shrinking the HOMO−LUMO gap, whereas the alkylthio ( 106c , E g = 1.36 eV) and carbomethoxy ( 106d , E g = 1.34 eV) substituents have an opposite effect.…”

Diels–Alder cycloaddition as an efficient tool for linking π-donors onto fullerene C60

“…In the thioxo series, classical reductive elimination or thermal treatment of the corresponding sulfone (route B) underwent easy access to the corresponding diene, whereas the selenoxo analog was accessible through route A [48]. Hetero-Diels-Alder reactions with C60 provided efficiently these 1,3-dithiole-C60 dyads 25(a-c) [44,45,49].…”

Highly Functionalized Tetrathiafulvalenes: Riding along the Synthetic Trail from Electrophilic Alkynes

“…Clearly this research area has been restricted by lack of suitable TTF building blocks. The approach developed by our group was based on the synthesis of precursors such as the vicinal bis(bromomethyl) 2-oxo (or 2-thioxo or 2-selenoxo)-1,3-dithioles 134 , which were able to smoothly undergo reductive elimination on treatment with naked iodide to give rise to dienes (Scheme ) . Unfortunately, attempts to complete a symmetrical trialkyl-phosphite-mediated coupling reaction or to use the dicobalt octacarbonyl method from the different 1,3-dithiole-C 60 systems 159 or 1,3-dithiolium-C 60 salts 160 to prepare the dumbbell 158 failed.…”