Department of Chemistry , Columbia University , New York , New York 10027 , United States.
Department of Chemistry , Binghamton University , Binghamton , New York 13902 , United States.
J Am Chem Soc. 2018 Mar 14;140(10):3523-3527. doi: 10.1021/jacs.8b00260. Epub 2018 Mar 6.
An enantioselective catalytic inverse-electron-demand Diels-Alder reaction of salicylaldehyde acetal-derived oxocarbenium ions and vinyl ethers to generate 2,4-dioxychromanes is described. Chiral pentacarboxycyclopentadiene (PCCP) acids are found to be effective for a variety of substrates. Computational and X-ray crystallographic analyses support the unique hypothesis that an anion with point-chirality-induced helical chirality dictates the absolute sense of stereochemistry in this reaction.
本文描述了一种对映选择性催化的逆电子需求 Diels-Alder 反应，即水杨醛缩醛衍生的氧杂碳正离子与乙烯基醚的反应，生成 2,4-二氧代色满。发现手性五羧基环戊二烯（PCCP）酸对于各种底物都是有效的。计算和 X 射线晶体学分析支持了一个独特的假设，即带有手性诱导螺旋手性的阴离子决定了这个反应中立体化学的绝对构型。
