NOVELTY - Preparing a benzofuran-2-carboxamide derivative (I) or its salt, comprises (ia) amidation of a benzofuran-2-carboxylic acid ester derivative (II) or its salt with ammonia in a solvent to produce (I), and optionally converting (I) into its salt, where the ammonia is used in the form of aqueous ammonia or ammonia gas, or ammonia saturated in an organic solvent.    USE - The process is useful for preparing (I) such as vilazodone, which is useful as a serotonergic antidepressant for treating major depressive disorder. No suitable example given.    ADVANTAGE - The process allows for rapid and simple preparation of (I) with high purity and yield in an environmental friendly manner.    DETAILED DESCRIPTION - Preparing a benzofuran-2-carboxamide derivative of formula (I) or its salt, comprises (ia) amidation of a benzofuran-2-carboxylic acid ester derivative of formula (II) or its salt with ammonia in a solvent to produce (I), and optionally converting (I) into the salt, where the ammonia is used in the form of aqueous ammonia or ammonia gas, or ammonia saturated in an organic solvent.    R = H, protecting group P1, or IND-Q- radical;    IND = indol-3-yl radical, 2,3-di-hydro-1H-indol-3-yl radical, or 2-oxo-2,3-di-hydro-1H-indol-3-yl radical (unsubstituted or mono- or polysubstituted by OH, OA, CN, X, COR1 or CH2R1);    Q = -(CH2)2-, -(CH2)3- or -(CH2)4-;    A = 1-6C-alkyl;    X = F, Cl, Br or I;    R1 = OH, OA, NH2, NHA or NA2; and    R2 = 1-4C-alkyl.    INDEPENDENT CLAIMS are included for:    (1) preparing an alkyl 5-(1-piperazinyl)benzofuran-2-carboxylate compound of formula (IIa) or its acid addition salt, comprising (i) reacting an alkyl 5-aminobenzofuran-2-carboxylate compound of formula (III) or its acid addition salt with a sulfonamide compound of formula (Cl-CH2-N(S(=O)(=O)(G))-(CH2)2-Cl) (IV) in the presence of a base to produce a sulfonyl piperazine compound of formula (V), and (ii) deprotecting (V) to produce (IIa) and optionally converting (IIa) into its salt;    (2) preparing vilazodone (Ib) or its salt comprising (a) reacting 5-cyanoindole (IX) with 4-chlorobutyryl chloride (X) in the presence of a Lewis acid in a solvent to produce a reaction mass, (b) isolating the compound from the reaction mass obtained in step (a), (c) reacting the compound obtained in step (b) with an alcohol or an aqueous alcohol to produce 3-(4-hydroxybutyryl)-1H-indole-5-carbonitrile (VIII) or its salt, (d) reducing (VIII) with a reducing agent in the presence of an acid to produce 3-(4-hydroxybutyl)-1H-indole-5- carbonitrile (VII) or its salt, (e) converting (VII) obtained in step (d) into its sulfonyl ester derivative of formula (VI) or its salt, (f) reacting (VI) with an alkyl 5-(1-piperazinyl)benzofuran-2-carboxylate compound of formula (IIa) or its acid addition salt in the presence of a base in a solvent to produce an alkyl 5-(4-(4-(5-cyanoindol-3-yl)butyl)piperazin-1-yl)benzofuran-2-carboxylate of formula (IIb) or its acid addition salt, and (g) amidation of (IIb) to produce (Ib), and optionally converting (Ib) into its salt;    (3) the compound (VIII) or its salt;    (4) preparing (VIII) or its salt, comprising the steps (a)-(c) as above per se;    (5) preparing (VII) or its salt, comprising the steps (a)-(d) as above per se;    (6) preparing (IIb) or its acid addition salt, comprising the step (f) as above per se; and    (7) preparing 3-(4-chlorobutyl)-1H-indole-5-carbonitrile (XII) or its salt, comprising (h) reducing 3-(4-chlorobutyryl)-1H-indole-5-carbonitrile (XIII) or its salt with sodium cyanoborohydride or sodium borohydride in the presence of chlorotrimethylsilane in a solvent to produce (XII) or its salt.    R3 = aryl (optionally substituted), alkyl, cycloalkyl, haloalkyl or aralkyl; and    G = alkyl, cycloalkyl or phenyl (all optionally substituted by alkyl, alkoxy, halo, nitro, amino or acetyl amino).