abstract |
The present invention relates to compounds of the formula I n n n n n n n n n n wherein X 1 , X 2 are O or C(CN) 2 ; A is selected from n n n n n n n n n n wherein, if present, X 3 , X 4 are O or C(CN) 2 and m, R 4a , R 4b , R 5a , R 5b , R 6a , R 6b , R 6c , R 6d , R 7a , R 7a , R 8a , R 8b , R 9 , R 10a , R 10b , R m1 , R m2 , R m3 and R m4 are as defined in the claims and description. The present invention also relates to a method for their preparation and their use as semiconductors, in particular as semiconductors in organic electronics and organic photovoltaics. |