straightforward and efficient synthesis of naphtho[1,8‐bc]pyran derivatives and related polycyclic compounds is achieved by the rhodium‐catalyzed oxidative coupling of 1‐naphthols or other phenolic and alcoholic substrates with alkynes. In these annulation reactions, the hydroxy groups effectively act as the key function for the regioselective CHbondcleavage.
萘并[1,8- bc ]吡喃衍生物和相关多环化合物的直接有效合成是通过1-萘酚或其他酚和醇底物与炔烃的铑催化氧化偶联而实现的。在这些环化反应中,羟基有效地充当区域选择性CH键裂解的关键功能。
Hydroxyl-Directed Ruthenium-Catalyzed C–H Bond Functionalization: Versatile Access to Fluorescent Pyrans
作者:Vedhagiri S. Thirunavukkarasu、Margherita Donati、Lutz Ackermann
DOI:10.1021/ol301387t
日期:2012.7.6
Hydroxyl-assisted oxidative annulations of alkynes were accomplished with an inexpensive ruthenium(II) complex, delivering fluorescent pyrans via highly site selective as well as chemo- and regioselective C-H/O-H bond functionalizations.
Oxidative [4 + 2] annulation of 1-naphthols with alkynes accelerated by an electron-deficient rhodium(<scp>iii</scp>) catalysts
作者:Antônio Junio Araujo Dias、Hiroto Takahashi、Juntaro Nogami、Yuki Nagashima、Ken Tanaka
DOI:10.1039/d1ob02181h
日期:——
The 1,3-diethoxycarbonyl-2,4,5-trimethylcyclopentadienyl (CpE) rhodium(III) complex displayed high efficacy in the catalytic oxidative annulation of 1-naphthols with internal alkynes under mild conditions. DFT calculations revealed that lower activation energies for the concerted metalation-deprotonation and the reductive elimination steps are the key to improved reactivity.
1,3-二乙氧基羰基-2,4,5-三甲基环戊二烯基(Cp E )铑( III )配合物在温和条件下对1-萘酚与内炔烃的催化氧化环化表现出高效。DFT 计算表明,协同金属化去质子化和还原消除步骤的较低活化能是提高反应性的关键。