To optimise the synthesis of 3a, a plethora of reaction conditions, including the catalysts, solvents, bases, temperature, humidity, and molar ratios, were extensively explored. Firstly, the effect of the catalyst, CoCl2, was investigated using Cs2CO3 as the base and acetone as the solvent (Table , entry 1), and both 3a and 5a were obtained in low yield. Next, CoCl2 was replaced with various catalysts, namely, FeCl3, Cu(CF3COO)2, Co(OAc)2, and CuO to ascertain the effect of the catalyst on product formation. Among these, Cu(CF3COO)2 emerged as the catalyst of choice, affording 3a in good yield within a reaction time of 4 h. Next, with Cu(CF3COO)2 as the optimal catalyst, the reaction media was varied and six distinct solvents, namely acetone, ethanol, THF, DMF, IPA, and EA, were assessed to ascertain product formation (Table , entries 6-11). The results clearly indicate that using acetone as the reaction solvent led to the highest yield (67%) of 3a (Table , entry 6) which further increased to 96% when the base was changed to DMAP. This particular reaction was also catalysed by 5 mol% Cu(CF3COO)2 and facilitated using mercury lamp irradiation (Table , entry 20). [i] DIPEA, N,N-diisopropylethylamine.