Treatment of the iododienynone 4 with Bu3SnH-AIBN results in the formation of the tricyclic enone 6 by way of radical-mediated macrocyclisation, to 5, followed by transannular Diels-Alder reaction. By contrast, similar treatment of 8 produced the tetracycle 12 (70%) rather than the Diels-Alder product 9, and the analogous system 13 gave rise to the novel tetracyclic diene-dione 18 presumably by way
所述iododienynone的治疗4与卜3 SNH-AIBN导致形成
三环烯酮6由自由基介导的大环化的方式,5,随后跨环Diels-Alder反应。与此相反,类似的治疗8产生的四环12(70%)而不是第尔斯-阿尔德产品9和模拟系统13就产生了新的四环二
烯二
酮18大概是由
中间体的方式14,16和17。