4-Cyclohex-2-enyl-3-hydroxy-1-methylquinolin-2(1H)-one (4) was prepared in 90% yield by the thermal [3,3]sigmatropic rearrangement of 3-cyclohex-2-enyloxy-1-methylquinolin-2(1H)-one (3) in refluxing chloroben-zene for 10 h. Compound (4) was cyclised through a sequence of reactions viz. i) acetylation ii) addition of bromine and iii) treatment of the acetyl dibromo compound (6) with base to give a bicyclic product (7) in 90% yield. Treatment of compound4with pyridine hydro-bromide perbromide in dichloromethane at 0–5° C afforded a cyclic product8in excellent yield. Compound4when treated with cold conc. sulphuric acid at 0–5° C furnished the bicyclic product 12 in 89% yield.