When compared to a long-straight chain terminal alkyne, a long chain terminal alkyne with a distal isopropyl unit (isobranched) isomerizes about two times faster when treated with strong base under identical conditions, and appears to follow pseudo first order kinetics. In both cases, equilibration to a 95–97:5–3 mixture of terminal:internal alkyne accompanies isomerization. The difference in rate may be due to an unusual folding of both long-chain alkynes, bringing the distal substituent close to the carbon-carbon-triple bond moiety. The distal isopropyl moiety may provide unanticipated steric hindrance that disrupts such folding, making the propargylic proton more available for reaction with base.

与长直链末端炔烃相比，带有远端异丙基单元（异支链）的长链末端炔烃在相同条件下用强碱处理时异构化速度快约两倍，并且似乎遵循伪一级动力学。在两种情况下，异构化都会使末端炔烃：内部炔烃平衡至95–97：5–3的混合物达到平衡。速率差异可能是由于两个长链炔烃异常折叠所致，使远端取代基接近碳-碳-三键部分。远端异丙基部分可能会提供无法预料的空间位阻，从而破坏此类折叠，从而使炔丙基质子更易于与碱反应。