反应详情

The reactions are also highly stereo- and regiospecific. Thus, thallation-carbonylation of cis- and trans-2-phenylcyclohexanoles (examples 7 and 8) provide exclusively the cis and trans fused tricyclic lactones respectively. Substituents on the aromatic ring are also observed to effect a very pronounced directive effect. For example, thallation-carbonylation of m-methoxybenzyl alcohol affords the 5-methoxyphthalide in 89% yield and only a trace of the 7-methoxyphthalide (example 4). Similarly, m-hydroxybenzyl alcohol affords a 95% isolated yield of pure 5-hydroxyphthalide (example 5).

1. customSimilarly, m-hydroxybenzyl alcohol affords a 95%