Synthesis with Perfect Atom Economy: Generation of Furan Derivatives by 1,3-Dipolar Cycloaddition of Acetylenedicarboxylates at Cyclooctynes
作者:Klaus Banert、Sandra Bochmann、Andreas Ihle、Oliver Plefka、Florian Taubert、Tina Walther、Marcus Korb、Tobias Rüffer、Heinrich Lang
DOI:10.3390/molecules190914022
日期:——
undergo, at room temperature, a 1,3-dipolar cycloaddition with dialkyl acetylenedicarboxylates 1a,b to generate furan-derived short-lived intermediates 2, which can be trapped by two additional equivalents of 1a,b or alternatively by methanol, phenol, water or aldehydes to yield polycyclic products 3b-d, orthoesters 4a-c, ketones 5 or epoxides 6a,b, respectively. Treatment of bis(trimethylsilyl) acetylenedicarboxylate
环辛炔和环辛烯-5-炔在室温下与乙炔二羧酸二烷基酯 1a,b 发生 1,3-偶极环加成反应,生成呋喃衍生的短寿命中间体 2,其可被另外两个等价物 1a,b 或或者通过甲醇、苯酚、水或醛分别产生多环产物 3b-d、原酸酯 4a-c、酮 5 或环氧化物 6a、b。用环辛炔处理双(三甲基甲硅烷基)乙炔二羧酸酯 (1c) 通过偶极中间体 2c 的逆布鲁克重排产生酮 7。在所有情况下,产品都是以完美的原子经济形成的。