a compound of formulae xiv m xiv n respectively wherein l 1 and l 2 are leaving groups such as alkoxy preferably methoxy ethoxy or benzyloxy more preferably methoxy or ethoxy wherein l 8 is a leaving group such as halo preferably iodo and l 3 is a suitable leaving group with a suitable base in a polar solvent according to methods analogous to the preparation of the compounds of formulae xii a xii l in the foregoing paragraph suitable leaving groups of the formula l 3 include halo para tolylsulfonyloxy ots or methylsulfonyloxy oms preferably l 3 is halo such as chloro the aforesaid reaction can be conducted at a temperature of about 0 u00b0 c to about 50 u00b0 c preferably about 20 u00b0 c for a period of about 1 hour to about 4 hours suitable solvents include tetrahydrofuran dimethylformamide and alcohol compounds of formula xiv a xiv n as defined above can be prepared by reacting a compound of formula xv with a compound of formula v i e a compound of formulae va vn respectively as defined in the description of scheme 1 above and wherein l 3 and l 4 are suitable leaving groups such as halo para tolylsulfonyloxy ots or methylsulfonyloxy oms preferably halo such as bromo.