Stereoselective Lateral Functionalization of Monosubstituted [2.2]Paracyclophanes by Directedortho-Metalation−Homologous Anionic Fries Rearrangement
作者:Thilo Focken、Henning Hopf、Victor Snieckus、Ina Dix、Peter G. Jones
DOI:10.1002/1099-0690(200106)2001:12<2221::aid-ejoc2221>3.0.co;2-3
日期:2001.6
the lateral functionalization of monosubstituted [2.2]paracyclophanes. After protection of the ortho site of an O-([2.2]paracyclophanyl) diisopropylcarbamate, an anionic Fries rearrangement resulted in a substitution of the benzylic position to give syn-4-hydroxy-N,N-diisopropyl-5-triethylsilyl-2-[2.2]paracyclophanecarboxamide (4b) with a syn/anti diastereoselectivity of more than 99:1. An alternate
已经开发了两种有效的途径用于单取代的[2.2]对环环烷的侧向官能化。在保护了O -([2.2]对环苯甲酰基)二异丙基氨基甲酸酯的邻位之后,阴离子弗里斯重排导致苄基位置的取代,得到了顺式-4-羟基-N,N-二异丙基-5-三乙基甲硅烷基-2-。 [2.2]对环苯甲酰胺(4b)具有超过99:1的顺/反非对映选择性。备选路线包括的横向位置的直接官能化ñ -叔丁基-4- [2.2] paracyclophanecarboxamide(9)通过定向金属化。发现该反应是高度立体选择性的,仅形成顺式异构体11。