Enantioselective Synthesis of Rigid 2-Aminotetralins. Utility of Silicon as an Oxygen and Nitrogen Surrogate in the Tandem Addition Reaction
作者:Andrew P. Degnan、A. I. Meyers
DOI:10.1021/jo0001131
日期:2000.6.1
Dimethylphenylsilyllithium undergoes a highly diastereoselective conjugate addition to chiral naphthyloxazoline 11. Electrophilic trapping of the resulting aza-enolate affords the tandem addition product (12) in high yields as a single diastereomer. The silicon, thus incorporated, may be protodesilylated and undergoes a Tamao oxidation to afford the corresponding alcohol. By chemical modification of the oxazoline
二甲基苯基甲硅烷基锂经历手性萘基恶唑啉11的高度非对映选择性共轭加成反应。亲电捕集所得的氮杂-烯醇酸酯可作为单个非对映异构体以高收率获得串联加成产物(12)。这样掺入的硅可以被去甲硅烷基化并进行塔毛氧化以提供相应的醇。通过恶唑啉的化学改性,制备了γ-内酯(28)和δ-内酯(37)。还原每种内酯,然后氧化随后的二醇,得到酮醛。1,4-二羰基的双还原胺化(来自γ-内酯)允许合成两个新颖的六氢苯并[e]吲哚,20和35。1,5-二羰基的双还原胺化(来自δ-内酯)接触了两种新颖的八氢苯并[f]喹啉,