Substituted tetrathiotetracenes and tetraselenotetracenes

Abstract

Substituted tetrathiotetracenes and tetraselenotetracenes of the formula I ##STR1## in which Z is --S-- or --Se-- and (a) R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are H and R.sup.5 to R.sup.8 are each H and at least one of the radicals R.sup.5 to R.sup.8 independently of one another is a substituent belonging to the group comprising C.sub.1 -C.sub.20 alkyl--X--.sub.p which is unsubstituted or substituted by halogen, --CN, --CONR.sup.9 R.sup.10, --OR.sup.9, --SR.sup.9 or --COOR.sup.9, with the exception of C.sub.1 -C.sub.4 alkyl and methoxy, C.sub.2 -C.sub.18 alkenyl--X--.sub.p, C.sub.2 -C.sub.18 -alkynyl--X--.sub.p, C.sub.3 -C.sub.8 cycloalkyl--X--.sub.p, (C.sub.1 -C.sub.12 alkyl)--C.sub.3 -C.sub.8 cycloalkyl--X--.sub.p, C.sub.3 -C.sub.8 cycloalkyl-C.sub.r H.sub.2r --X--.sub.p, (C.sub.1 -C.sub.12 alkyl)-C.sub.3 -C.sub.8 -cyclo alkyl-C.sub.r H.sub.2r --X--.sub.p, phenyl--X--.sub.p, (C.sub.1 -C.sub.12)alkyl)-phenyl--X--, phenyl-C.sub.r H.sub. 2r --X--.sub.p and (C.sub.1 -C.sub.12 alkyl)-phenyl-C.sub.r H.sub.2r --X--.sub.p, r is 1 or 2 and p is 0 or 1 and X is --O--, --S--, --SO-- or --SO.sub.2 --, or R.sup.5 to R.sup.8 independently are a substituent belonging to the group comprising --Br, --CF.sub.3, --CN, --Si(C.sub.1 -C.sub.4 alkyl).sub.3, --S--(C.sub.m H.sub.2m O)--.sub.n R.sup.11 or --O--C.sub.m H.sub.2m --O--R.sup.11, or each one of R.sup.5 to R.sup.8 is --F or --Cl and at least one further member of R.sup.5 to R.sup.8 is a substituent of the groups defined above, including C.sub.1 -C.sub.4 alkyl and methoxy, R.sup.9 and R.sup.10 independently of one another are H, C.sub.1 -C.sub.12 alkyl, phenyl or --C.sub.m H.sub.2m --O--.sub.q R.sup.11, or R.sup.9 and R.sup.10 together are tetramethylene, pentamethylene, 3-oxapentylene or --CH.sub.2 CH.sub.2 NR.sup.9 CH.sub.2 CH.sub.2 --, R.sup.11 is H or C.sub.1 -C.sub.12 -alkyl, m is a number from 2 to 4, n is a number from 2 to 20 and q is a number from 1 to 20, or