Value of zeolites in asymmetric induction during photocyclization of pyridones, cyclohexadienones and naphthalenones
作者:Karthikeyan Sivasubramanian、Lakshmi S. Kaanumalle、Sundararajan Uppili、V. Ramamurthy
DOI:10.1039/b702572f
日期:——
approaches, have been examined within zeolites with the aim of achieving asymmetric induction during the photocyclization of cyclohexadienone, naphthalenone and pyridone derivatives. Within zeolites, enantioselectivity as high as 55% and diastereoselectivity as high as 88% have been obtained. The observed stereoselectivities are significant given the fact that these reactions gave very little stereoselectivities
为了在环己二烯酮,萘酮和吡啶酮衍生物的光环化过程中实现不对称诱导,已经在沸石中研究了两种策略,即手性诱导剂和手性辅助方法。在沸石中,对映选择性高达55%,非对映选择性高达88%。考虑到这些反应在各向同性溶液介质中几乎没有立体选择性,因此观察到的立体选择性非常重要。沸石中二烯酮,萘酮和N-烷基吡啶酮的光环化获得的结果补充了我们先前对托酚酮衍生物的光环化,1,2-二苯基环丙烷和2,3-二苯基-1-苯甲酰基环丙烷的几何异构化以及α-氧代酰胺的Norrish II型反应,苯基金刚烷基酮,苯基降冰片基酮和苯基环己基酮。在这些例子的帮助下,我们已经确定了沸石及其电荷补偿阳离子在光化学反应中实现不对称诱导的重要性。