<i>tert</i>-Butyl-Substituted Tripyrranes: Insights into the Steric and Conformational Factors that Influence Porphyrinoid Ring Formation in the “3 + 1” Methodology
作者:Wenhua Jiao、Timothy D. Lash
DOI:10.1021/jo0207628
日期:2003.5.1
conformation in solution has been radically altered by the presence of these tert-butyl moieties. This appears to be the first time that the NMR properties of an intermediate in porphyrin or porphyrin analogue synthesis have been correlated to its effectiveness in macrocycle formation.
用于卟啉类化合物合成的MacDonald“ 3 +1”路线涉及三吡喃与单环二醛的酸催化缩合,然后进行氧化步骤。在本研究中,发现将叔丁基取代基引入三联吡喃单元时,收率大大降低。对三吡喃的质子NMR光谱分析表明,这些叔丁基部分的存在已彻底改变了溶液中的优选构象。这似乎是第一次将卟啉或卟啉类似物合成中的中间体的NMR特性与其在大环形成中的有效性相关联。