AbstractStar‐shaped alkylaromatic hydrocarbons consisting of oligomeric naphthalene cores and long straight‐chain alkyl arms have been synthesised using a one‐pot method:Where 1‐alkene is 1‐hexene, 1‐octene, 1‐decene, 1‐dodecene, 1‐tetradecene, 1‐hexadecene, and 1‐octadecene, respectively. Different linear 1‐alkenes with increasing chain length have been reacted with naphthalene oligomers in an identical way, and the properties of the total products compared and related to the chain length of the alkylating normal 1‐alkene. Consequent to this, increases in M̌n, (= 550–1900), viscosity indexes (90–161), pour points (—24 to + 17°C), flash points (210–330°C), and oxidation resistance, could be observed. These products exhibited properties good enough to be suitable for use as lu