Process for preparing benzoic acid derivative intermediates and benzothiophene pharmaceuticals

A process for preparing a compound of formula Ib ##STR11## which comprises preparing a compound of formula VI ##STR12## wherein:

• R.sup.1 and R.sup.2 each are independently C.sub.1 -C.sub.4 alkyl, or R.sup.1 and R.sup.2 together with the nitrogen to which they are attached form a piperidinyl, pyrrolidinyl, methylpyrrolidinyl, dimethylpyrrolidinyl, morpholino, dimethylamino, diethylamino, or 1-hexamethyleneimino ring;
• n is 2 or 3;
• and
• Y.sup.1 is p toluenesulfonyl O, methylsulfonyl O, trifluoromethylsulfonyl-O-, 2,2,2-trifluoroethylsulfonyl-O-, or trifluoroacetyl-O-;
• or a salt or solvate thereof, by reacting a hydroxylamine of formula III ##STR13## with a compound selected from the group consisting at W.sub.2 O, and W-halo, wherein W is selected from the group consisting of p toluenesulfonyl, methylsulfonyl, trifluoromethylsulfonyl, 2,2,2-trifluoroethylsulfonyl, and trifluoroacetyl;
• and further reacting a compound of formula VI with a compound of formula IV ##STR14## wherein R.sup.6 is a carboxy protecting group, in the presence of an alkyl acetate solvent and a suitable base.