18181-25-4Relevant articles and documents
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Weiss,Knapp
, p. 61,65 (1932)
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The p: K a values of N-aryl imidazolinium salts, their higher homologues, and formamidinium salts in dimethyl sulfoxide
Cole, Marcus L.,Dunn, Michelle H.,Harper, Jason B.,Konstandaras, Nicholas,Luis, Ena T.
, p. 1910 - 1917 (2020/03/23)
A series of imidazolinium salts, their six-, seven- A nd eight-membered homologues, and the related formamidinium salts were prepared, and their pKa values were determined in DMSO at 25 °C using the bracketing indicator method. The effect of each type of structural variation on the acidity of each salt was considered, particularly noting the importance of ring size and the effect of the steric and electronic nature of the N-aryl substituents. The effect of a cyclic structure was also probed through comparing the cyclic systems with the corresponding formamidinium salts, noting the importance of conformational flexibility in the latter cases. Along with allowing choice of appropriate bases for deprotonation of these species, it is anticipated that the data presented will aid in the understanding of the nucleophilicity, and potentially catalytic efficacy, of the corresponding carbenes.
Solvent control of product diversity in palladium-catalyzed addition of arylboronic acid to aryl aldehydes
Das, Tuluma,Chakraborty, Amarnath,Sarkar, Amitabha
, p. 5174 - 5178 (2014/12/10)
In Pd-catalyzed arylboronic acid addition to aryl aldehydes, the expected carbinol or asymmetrical ether can be obtained as the major product by altering aqueous solvent composition. Exploiting this methodology with 2-formylbiphenyls as reaction partner, a fluorene scaffold can be readily constructed in two steps.
Palladium-catalyzed arylation of methylene-bridged polyarenes: Synthesis and structures of 9-arylfluorene derivatives
Chen, Jheng-Jhih,Onogi, Satoru,Hsieh, Ya-Chu,Hsiao, Chien-Chi,Higashibayashi, Shuhei,Sakurai, Hidehiro,Wu, Yao-Ting
supporting information; experimental part, p. 1551 - 1558 (2012/07/17)
In the presence of a catalytic system comprised of palladium(II) acetate and tricyclohexylphosphine, the reaction of fluorene with haloarenes generated 9-arylfluorenes in good to excellent yields. The scope and limitations of the coupling reaction were investigated. This synthetic protocol is more efficient than conventional methods. A wide range of functional groups, including alkyl, alkoxy, ester, and nitrile, can tolerate the reaction conditions herein. Sterically congested haloarenes also gave satisfactory results. Furthermore, this synthetic method is utilized to prepare 9,9-diarylfluorenes and tetraarylindenofluorene. Depending on the reaction conditions, the arylation of bowl-shaped sumanene gave monoarylated sumanene either as the sole product or with another diaryl-substituted product. Copyright
