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The easily obtainable 5‐chloro‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehydes 2 were used as precursors in Sonogashira‐type cross‐coupling reactions with various alkynes to provide the corresponding 5‐alkynyl‐1H‐pyrazole‐4‐carbaldehydes 3. Treatment of these with tert‐butylamine with microwave assistance afforded the corresponding 1‐phenylpyrazolo[4,3‐c]pyridines 4. The oximes 5 – derived from the aldehydes 3 – were transformed into the corresponding 1‐phenylpyrazolo[4,3‐c]pyridine 5‐oxides 6 through silver‐triflate‐catalysed regioselective cyclisation. Ring closure of the oximes 5 in the presence of iodine in ethanol gave the 7‐iodo‐1‐phenylpyrazolo[4,3‐c]pyridine 5‐oxides 7. Detailed NMR spectroscopic investigations were undertaken with all obtained products.

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