574-47-0Relevant academic research and scientific papers
Palladium-catalyzed coupling reaction of 2-iodobiphenyls with alkenyl bromides for the construction of 9-(diorganomethylidene)fluorenes
Zhao, Ya-Heng,Wang, Jian-Long,Zhou, Yun-Bing,Liu, Miao-Chang,Wu, Hua-Yue
supporting information, p. 8250 - 8253 (2021/10/12)
An atom economical protocol for the construction of 9-(diorganomethylidene)fluorenes through palladium-catalyzed coupling reactions of 2-iodobiphenyls with alkenyl bromides has been reported. The reaction proceeds through the C-H activation/oxidative addition/reduction elimination/intramolecular Heck coupling reaction to afford a series of 9-(diorganomethylidene)fluorenes with good yields. Control experiments demonstrate that a five-membered palladacycle acts as a key intermediate and β-H elimination serves as the rate-limiting step.
An N-heterocyclic carbene-catalyzed switchable reaction of 9-(trimethylsilyl)fluorene and aldehydes: Chemoselective synthesis of dibenzofulvenes and fluorenyl alcohols
Ma, Yu-Chuan,Luo, Jin-Yun,Zhang, Shi-Chu,Lu, Shu-Hui,Du, Guang-Fen,He, Lin
supporting information, p. 3717 - 3721 (2021/05/04)
An N-heterocyclic carbene-catalyzed synthesis of dibenzofulvenes and fluorenyl alcohols was developed. In the presence of 10 mol% NHC (1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) and 4 ? molecular sieves, 9-(trimethylsilyl)fluorene undergoes an olef
Ligand-Free Ru-Catalyzed Direct sp3 C-H Alkylation of Fluorene Using Alcohols
Shaikh, Moseen A.,Agalave, Sandip G.,Ubale, Akash S.,Gnanaprakasam, Boopathy
, p. 2277 - 2290 (2020/02/04)
The sp3 C-H alkylation of 9H-fluorene using alcohol and a Ru catalyst via the borrowing hydrogen concept has been described. This reaction was catalyzed by the [Ru(p-cymene)Cl2]2 complex (3 mol %) and exhibited a broad reaction scope with different alcohols, allowing primary and secondary alcohols to be employed as nonhazardous and greener alkylating agents with the formation of environmentally benign water as a byproduct. A variety of 9H-fluorene underwent selective and exclusive mono-C9-alkylation with primary alcohols in good to excellent isolated yield (26 examples, 50-92% yield), whereas this reaction with secondary alcohols in the absence of any external oxidants furnished the tetrasubstituted alkene as the major product. Furthermore, a base-mediated C-H hydroxylation of the synthesized 9H-fluorene derivatives afforded 9H-hydroxy-functionalized quaternary fluorene derivatives in excellent yield.
Intermolecular oxidative Friedel-Crafts reaction triggered ring expansion affording 9,10-diarylphenanthrenes
Jin, Tienan,Yang, Lu,Gridnev, Ilya D.,Terada, Masahiro
supporting information, p. 8920 - 8924 (2020/12/02)
A novel intermolecular tandem oxidative aromatic coupling between arylidene fluorenes and unfunctionalized aromatics mediated by a DDQ/TFA oxidation system has been developed for the construction of 9,10-diary-lphenanthrenes (DAPs). The formation of a benzylic carbocation species possessing a quaternary sp3-carbon center on the fluorene moiety by an intermolecular oxidative Friedel-Crafts reaction of two different arenes successfully triggered the subsequent ring expansion to afford DAPs.
Dications of benzylidenefluorene and diphenylmethylidene fluorene: The relationship between magnetic and energetic measures of antiaromaticity
Do, Catherine,Hatfield, Julianne,Patel, Shirali,Vasudevan,Tirla, Cornelia,Mills, Nancy S.
supporting information; experimental part, p. 181 - 187 (2011/03/19)
Oxidation of m- and p-substituted benzylidene fluorenes to antiaromatic dications was attempted by electrochemical and chemical means. Electrochemical oxidation to dications was successful for benzylidene fluorenes with p-methoxy, p-methyl, p-fluoro, and
Potassium fluoride supported on alumina induced aldol condensation of fluorene
Lu, Wen-Xing,Yan, Chao-Guo,Yao, Rong
, p. 3719 - 3723 (2007/10/03)
In the presence of potassium fluoride supported on alumina as a solid base, fluorene condensated smoothly with aromatic aldehydes in DMF at 150°C to give dibenzofulvenes in fair yield (44-90%).
