Under these conditions, the scope of this isomerization reaction is illustrated in Table 1.‡ Thus, substrates with a bulky primary alkyl group and ethyl group on the alkyne selectively provide terminal 1,3-dienes in 76–84% yield (entries 1–3). Alkynes with a secondary alkyl group and ethyl group are also isomerized to terminal 1,3-dienes selectively (entry 4). Alkynes bearing a longer alkyl substituent can also be employed to furnish internal 1,3-diene products, ...
