NOVELTY - Preparing (P1) n-butyraldehyde and/or n-butanol comprises: reacting 1,3-butadiene and amine (I) in presence of compound of VIIIb element of periodic table, e.g. alkali metalamide to give mixture of adducts (II) and (III); (b) isomerizing adduct (III) to adduct (II); (c) isomerizing (II) in presence of e.g. heterogeneous transition metal-containing catalyst in gas phase to give enamine (IV); and (d) reacting (IV) with e.g. water in presence of heterogeneous transition metal-containing catalyst in gas phase, and acid, where (I) is liberated that is recycled to the reaction stage of (a).    USE - The process is useful for preparing n-butyraldehyde and/or n-butanol (preferably 2-ethylhexanol) (claimed) which is useful for preparing plasticizer alcohols (plasticizer bis(2-ethylhexyl)phthalate), and as solvent for coating composition.    ADVANTAGE - The process: is suitable for large industrial scale production of n-butyraldehyde and/or n-butanol; provides n-butyraldehyde and/or n-butanol at high yields; achieves a higher degree of selectivity in the combined hydrolysis/hydrogenation of (IV) to n-butanol; and allows degree of activity and selectivity, and is flexible (butyraldehyde and/or 1-butanol as require), and provides low by-products and is cost-effective. In the process: unconverted 1,3-butadiene is recycled; and the conversion of step (c) to (d) is a single process stage without using additional solvents.    DETAILED DESCRIPTION - Preparing (P1) n-butyraldehyde and/or n-butanol comprises: (a) reacting 1,3-butadiene with amine of formula (R1R2NH) (I) at elevated temperature and at superatmospheric pressure in the presence of a compound of VIIIb element of the periodic table, in the presence of an alkali metalamide or basic metal oxide to give a mixture of the adducts of formulae (CH3-CH=CH-CH2-NR1R2) (II) and (CH=CH-CH(NR1R2)-CH3) (III); (b) isomerizing adduct (III) to the adduct (II); (b) isomerizing the adduct (II) in the presence of a homogeneous or heterogeneous transition metal catalyst in the liquid phase or heterogeneous transition metal-containing catalyst in the gas phase to give enamine of formula (CH3-CH2-CH=CH-NR1R2) (IV); and (c) reacting (IV) with hydrogen and water or water in the presence of homogeneous or heterogeneous transition metal catalyst in the liquid phase, heterogeneous transition metal-containing catalyst in the gas phase, and acid or one of the catalysts and an acid to give n-butyraldehyde and/or n-butanol, where (I) is liberated that is recycled to the reaction stage of (a).    Either R1, R2 = optionally substituted aliphatic or cycloaliphatic, aryl or aralkyl or H; or    NR1R2 = bridge member which optionally carry heteroatoms.    An INDEPENDENT CLAIM is also included for preparing (P2) 2-ethylhexanol, comprising: step (a) as above per se; (b1) isomerizing adduct (III) to the adduct (II); (c1) isomerizing the adduct (II) in the presence of a homogeneous transition metal catalyst in the liquid phase to give (IV); (d1) reacting (IV) with hydrogen and water, or water in the presence of the catalyst used in step (c1) and acid to give n-butyraldehyde; (e1) converting the n-butyraldehyde into the aldol product 2-ethylhex-2-enal; (f1) hydrogenating 2-ethylhex-2-enal to 2-ethylhexanol, where (I) is liberated again and the liberated (I) is recycled to the reaction according to step (a).