NOVELTY - Substituted 2-(4-(1,1-dihydroxybutyl)phenyl)-2-methylpropanoic acid compounds (V) are new.    USE - (V) are useful for preparing (VI) which are useful for preparing fexofenadine (all claimed), where the fexofenadine is useful as oral antihistamine agent, and for treating symptoms of allergic reactions, and symptoms related to the release of histamine comprising capillary dilatation, capillary permeability and vasodilatation, local erythemas, local edemas (swellings) and rashes, itching and, increase of salivary and bronchial gland secretion. No biological data given.    ADVANTAGE - (V) synthesizes fexofenadine which: does not require the use of toxic reagents such as mercury salts or expensive reagents such as palladium salts; allows easy handling reaction conditions with low environmental impact; and has less side effects.    DETAILED DESCRIPTION - Substituted 2-(4-(1,1-dihydroxybutyl)phenyl)-2-methylpropanoic acid compounds of formula (V) are new.    Either R1-R3 = linear or branched 1-20C alkyl (preferably R1-R3 are CH3); and    R4 = halo or OH; or    R2R3 = 5 or 6 membered ring comprising 1,3-dioxolane-2,2-diyl, 1,3-dioxane-2,2-diyl or 2,2-dimethyl-1,3-dioxane-5,5-diyl; or    OR2R4 = 5 membered ring comprising substituted tetrahydrofuran moiety of formula (IA).    INDEPENDENT CLAIMS are also included for:    (1) preparing (V);    (2) preparing substituted 2-(4-butyrylphenyl)-2-methylpropanoic acid compounds of formula (VI), comprising reacting substituted 2-(4-but-1-ynylphenyl)-2-methylpropanoic acid compounds of formula (IIa) with a hydrogen halide solution in solvent at 3-50 degrees C;    (3) synthesizing (s1) fexofenadine, comprising reacting (V) with aqueous hydrobromic acid or acetic acid in the presence of solvent to give (VI), and transforming the (VI) into fexofenadine;    (4) synthesizing (s2) fexofenadine, comprising (a1) transforming (VI) into substituted (2-(4-butylphenyl)-2-methylpropanoyl)oxy compounds of formula (V1c) by reaction with a trialkyl orthoformate in an alcoholic solvent in the presence of acid catalyst at 25 degrees C to the reflux temperature of the solvent, (b1) reacting the resultant (V1c) with azacyclonol in a solvent in the presence of a base at 20 degrees C to the reflux temperature of the solvent, followed by the optional saponification and by the optional subsequent treatment with acetic acid to give substituted 2-(4-(1,1-dihydroxy-4-(4-(hydroxydiphenylmethyl)piperidin-1-yl)butyl)phenyl)-2-methylpropanoic acid compounds of formula (VII), (c1) reacting (VII) with an aqueous acid in the presence of solvent at 20-40 degrees C to give substituted 2-(4-(4-(4-(hydroxydiphenylmethyl)piperidin-1-yl)butanoyl)phenyl)-2-methylpropanoic acid compounds of formula (VIII), and (d1) transforming the resultant (VIII) into fexofenadine;    (5) methyl 2-(4-(4-(4-(hydroxydiphenylmethyl)piperidin-1-yl)-1,1-dimethoxybutyl)phenyl)-2-methylpropanoate (VIIa); and    (6) 2-(4-(4-(4-(hydroxydiphenylmethyl)piperidin-1-yl)-1,1-dimethoxybutyl)phenyl)-2-methylpropanoic acid (VIIc).    R4a = halo preferably Cl or Br;    R5, R6 = linear or branched 1-20C alkyl (preferably CH3);    R1a = H or linear or branched 1-20C alkyl (preferably CH3).