A New Germanium-Based Linker for Solid Phase Synthesis of Aromatics: Synthesis of a Pyrazole Library
作者:Alan C. Spivey、Christopher M. Diaper、Harry Adams、Andrew J. Rudge
DOI:10.1021/jo000401x
日期:2000.8.1
An efficient synthesis of chlorogermane linker 12 is described. Economic introduction of germanium into this linker is accomplished by insertion of dichlorogermylene [from germanium(IV) chloride] into the homobenzylic C-Cl bond of 4-(2-chloroethyl)phenol 1. Using linker 12, transmetalation with lithiated 4-acetophenone, 3-acetophenone, and 4-(4'methoxy)biphenyl followed by Mitsunobu-type coupling to
描述了氯锗烷接头12的有效合成。通过将二氯锗苯[来自氯化锗(IV)]插入4-(2-氯乙基)苯酚1的均苄基C-Cl键中,可将锗经济引入该连接基中。使用连接基12,使用锂化的4-苯乙酮进行重金属化, 3-苯乙酮和4-(4'甲氧基)联苯,然后通过Mitsunobu型偶联到Argogel,分别得到官能化的树脂14、16和18。用TFA,ICl,Br2或NCS处理树脂18会产生干净的ipso-去甲酰化反应,分别释放出联苯19-22。树脂14和16用于通过烯胺酮形成(使用Bredereck试剂),缩合的闭环(使用一系列单取代的肼)和裂解(使用TFA和Br2)并行合成吡唑库。