| abstract |
The present invention provides the compounds of formulae (3) and (1) wherein n is 0 or 1, R 13 and R 14 are the same or different and are selected from the group consisting of NHR 310 , NR 311 R 312 , OR 313 , SR 314 and R 315 , or R 13 and R 14 together are selected from the group consisting of (a), (b) and (c), and X is CI, Br of I, and a process for the preparation of compounds of formula (3) comprising the compounds of formula (1) as key intermediates. |