Department of Applied Chemistry for Environment, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan.
Chem Commun (Camb). 2020 Dec 7;56(95):14988-14991. doi: 10.1039/d0cc06620f.
Herein, a simple and practical method for generating isoacenofuran, a new π-extended quinoidal building block, was developed. A three-step protocol involving double nucleophilic additions of alkynyllithiums to acene-2,3-dicarbaldehyde, mono-oxidation, and acid-promoted cyclization enables the generation of the target molecule, which is trapped by a dienophile to produce highly condensed acenequinones. Further transformations by double nucleophilic additions of alkynyllithium to hexacenequinone, followed by reductive aromatization, produce tetraalkynylhexacenes with a remarkably higher stability than that of the previously reported substituted hexacenes.
本文开发了一种简单实用的方法来生成异吖[并]呋喃，这是一种新的π-扩展醌式构筑块。该方法涉及炔基锂对并二萘-2,3-二醛的双亲核加成、单氧化和酸促进的环化三步反应，可生成目标分子，该分子被亲二烯体捕获，生成高度稠合的并二萘醌。通过六并二萘醌与炔基锂的双亲核加成，再进行还原芳构化，进一步转化，得到了四炔基六并苯，其稳定性明显高于以前报道的取代六并苯。
