The Effect of the Gem‐Dimethyl Unit in the Gold‐Catalyzed Cycloisomerization of Aliphatic 1‐Bromoalkynes

The introduction of the gem‐dimethyl unit in different positions resulted in sharp conformational effects in the gold‐catalyzed cycloisomerization of aliphatic 1‐bromoalkynes. Additionally, the cyclopropane unit has been used as an isostere of the gem‐dimethyl unit. Surprisingly, in this context, such replacement was unsuccessful. The experimental observations were rationalized with the aid of density functional theory (DFT) calculations.