Treatment of the o-ethynylbenzoic acids 1A with a catalytic amount of Pd(II) and triethylamine resulted in the 6-endo-dig cyclization to give the 3-substituted isocoumarins 3 as major products in moderate to good yields. Similarly, the palladium-catalyzed cyclization of o-ethynylbenzamides 1B also proceeded but afforded only the isoquinolin-1-ones 3B.

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Treatment of 2, 2′‐dibromodiphenylacetylene 7 with tert‐butyllithium followed by tellurium insertion resulted in intramolecular ring closure to afford [1]benzotelluro[3,2‐b][1]benzotellurophene 8a. Similarly, [1]benzoseleno‐[3,2‐b][1]benzoselenophene 8b and [1]benzothieno[3,2‐b][1]benzothiophene 8c were also obtained.