| abstract |
The present invention provides the compounds of formulae (3) and (1 ) wherein n is 0 or 1, R13 and R14 are the same or different and are selected from the group consisting of NHR310, NR311R312, OR313, SR314 and R315, or R13 and R14 together are selected from the group consisting of (a), (b) and (c), and X is CI, Br ot I, and a process for the preparation of compounds of formula (3) comprising the compounds of formula (1 ) as key intermediates. |