描述了铑 (I) 催化合成转化的研究,包括选择性断裂 C-C 键 α 到环丁酮的羰基。用等摩尔量的 (Ph3P)3RhCl 在甲苯中回流处理环丁酮时发生脱羰,得到相应的环丙烷。环丙烷的形成表明,Rh(I) 在初始步骤中插入了羰基碳和 α-碳之间的键。还实现了环丁酮的催化脱羰。反应的模式和速率很大程度上取决于铑(I)配合物的配体。When a cyclobutanone bearing a hydrogen atom at the 3-position was used, appropriate choice of the catalyst system led to the selective formation of either a cyclopropane or an alkene. 碳-碳键的断裂接下来与氢解结合。当环丁酮在氢气压力下用催化量的具有双齿双膦的铑(I)配合物处理时..
Friedel–Crafts Alkylation of Aromatics by TiCl4-Promoted Ring Cleavage of 3-Arylcyclobutanones
作者:Jun-ichi Matsuo、Mayu Kanie、Tomoyuki Yoshimura
DOI:10.1055/s-0036-1591497
日期:2018.2
his 90th birthday Abstract Ring cleavage of 3-arylcyclobutanones and successive Friedel–Craftsalkylation of methoxy- or alkyl-substituted benzene derivatives proceeded to give 3,3-diarylbutan-2-ones by activation with titanium tetrachloride. Ring cleavage of 3-arylcyclobutanones and successive Friedel–Craftsalkylation of methoxy- or alkyl-substituted benzene derivatives proceeded to give 3,3-diarylbutan-2-ones
Various 3-phenylcyclobutanones reacted with aliphatic and aromatic nitriles in the presence of Me3SiOTf to afford dihydropyridones by formal [4+2] cycloaddition.
cycloaddition between 3-ethoxy-2-alkylcyclobutanones and nitrosobenzene proceeded by activation with Me 3 SiOTf to afford 6-alkyl-2-phenyl-2 H -1,2-oxazin-5(6 H )-one by regioselective cleavage of the more substituted C2–C3 bond of the cyclobutanone ring. On the other hand, reactions of 3-phenylcyclobutanones and 2-benzyloxycyclobutanone with nitrosobenzene gave γ,δ-unsaturated and cyclic hydroxamic acid derivatives
3-乙氧基-2-烷基环丁酮和亚硝基苯之间的正式[4+2]环加成反应通过用Me 3 SiOTf活化得到6-烷基-2-苯基-2 H -1,2-恶嗪-5(6 H )-one通过区域选择性裂解环丁酮环上更多取代的 C2-C3 键。另一方面,3-苯基环丁酮和2-苄氧基环丁酮与亚硝基苯的反应分别通过环丁酮C1-C2键的断裂产生γ,δ-不饱和和环状异羟肟酸衍生物。
Formal [4 + 4] cycloaddition of 3-arylcyclobutanones with anthracene and their acid-promoted intramolecular cyclization with skeletal rearrangement
A reaction of 3-arylcyclobutanones with anthracene in the presence of TiCl4 gave 14-aryl-9,10-dihydro-9,10-butanoanthracen-12-ones as a formal [4 + 4] cycloadduct of anthracenes with a C4 unit formed by cleaving the more substituted C2C3 bond of cyclobutanones. On the other hand, activation of 3-arylcyclobutanones with TfOH in the absence of nucleophiles gave 2-tetralones with skeletal rearrangement
Catalytic enantioselective synthesis of benzocyclobutenols and cyclobutanols <i>via</i> a sequential reduction/C–H functionalization
作者:Jun Chen、Zhan Shi、Chunyu Li、Ping Lu
DOI:10.1039/d1sc02119b
日期:——
We report here a sequential enantioselective reduction/C–H functionalization to install contiguous stereogenic carbon centers of benzocyclobutenols and cyclobutanols. This strategy features a practical enantioselective reduction of a ketone and a diastereospecific iridium-catalyzed C–H silylation. Further transformations have been explored, including controllable regioselective ring-opening reactions