Reversing the regioselectivity of the renowned Diels–Alder reaction by overriding the usual thermodynamic and kinetic governing factors has always been a formidable challenge to synthetic organic chemists. Anthracenes are well-known to undergo [4 + 2]-cycloadditions with dienophiles at their 9,10-positions (central ring) over 1,4-positions (terminal ring) guided by the relative aromatic stabilization energy of the two possible products, and also by harboring the largest orbital coefficients of the highest occupied molecular orbital (HOMO) at the 9,10-positions. We, herein, report a 1,4-selective [4 + 2]-cycloaddition strategy of 9,10-unsubstituted anthracenes by installing electron-donating substituents on the terminal rings which is heretofore unprecedented to the best of our knowledge. The developed synthetic strategy does not require any premeditated engagement of the 9,10-positions either with any sterically bulky or electron-withdrawing substituents and allows delicate calibration of the regioselectivity by modulating the electron-donating strength of the substituents on the terminal rings. Likewise, the regioselective functionalization of the terminal anthracene ring in electrophilic substitution reactions is demonstrated. A mechanistic rationale is offered with the aid of detailed computational studies, and finally, synthetic applications are presented.

通过超越通常的热力学和动力学控制因素来逆转著名的 Diels-Alder 反应的区域选择性一直是合成有机化学家面临的巨大挑战。众所周知，蒽会在 9,10 位（中心环）和 1,4 位（端环）上与亲二烯体发生 [4 + 2]-环加成反应，这取决于两种可能产物的相对芳族稳定能，并且还通过在 9,10 位置包含最高占据分子轨道 (HOMO) 的最大轨道系数。我们在此报告了 9,10-未取代蒽的 1,4-选择性 [4 + 2]-环加成策略，方法是在末端环上安装供电子取代基，据我们所知，这是前所未有的。开发的合成策略不需要 9,10 位与任何空间庞大或吸电子取代基的任何预谋接合，并允许通过调节末端环上取代基的供电子强度来精确校准区域选择性。同样，证明了亲电取代反应中末端蒽环的区域选择性功能化。在详细的计算研究的帮助下提供了一个机械原理，最后，提出了综合应用。证明了亲电取代反应中末端蒽环的区域选择性功能化。在详细的计算研究的帮助下提供了一个机械原理，最后，提出了综合应用。证明了亲电取代反应中末端蒽环的区域选择性功能化。在详细的计算研究的帮助下提供了一个机械原理，最后，提出了综合应用。