525-64-4Relevant articles and documents
Fluorous mixture synthesis of fluorous-Fmoc reagents using a one-pot double tagging strategy
Sugiyama, Yuya,Ishihara, Kazuki,Masuda, Yuka,Kobayashi, Yuki,Hamamoto, Hiromi,Matsugi, Masato
, p. 2060 - 2062 (2013)
The concise synthesis of fluorous Fmoc (f-Fmoc) reagents bearing C 3F7 or C4F9 or C6F 13 chains were achieved by fluorous mixture synthesis. The fluorous tagging process was effectively conducted using Heck type reaction of the bis-diazonium salt and the corresponding fluorous olefine, each bearing a different fluorous tag, by a one-pot double tagging strategy. At the final stage, each f-Fmoc reagent was separated from the mixture of three f-Fmoc reagents by fluorous solid phase extraction.
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Schultz,G.
, (1880)
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An expeditious and highly efficient synthesis of substituted pyrroles using a low melting deep eutectic mixture
Alvi, Shakeel,Ali, Rashid
, p. 9732 - 9745 (2021/12/01)
An expeditious green method for the synthesis of diverse valued substituted pyrroles through a Paal-Knorr condensation reaction, using a variety of amines and 2,5-hexanedione/2,5-dimethoxytetrahydrofuran in the presence of a low melting mixture ofN,N’-dimethylurea andL-(+)-tartaric acid (which acts as a dual catalyst/solvent system), has fruitfully been revealed. Herein, we have disclosed the applicability of this simple yet effective strategy for the generation of mono- and dipyrroles in good to excellent yields. Moreover,C3-symmetric tripyrrolo-truxene derivatives have also been assembled by means of cyclotrimerization, Paal-Knorr and Clauson-Kaas reactions as crucial steps. Interestingly, the melting mixture was recovered and reused with only a gradual decrease in the catalytic activity (over four cycles) without any significant drop in the yield of the product. This particular methodology is simple, rapid, environmental friendly, and high yielding for the generation of a variety of pyrroles. To the best of our knowledge, the present work reveals the fastest greener method reported up to this date for the construction of substituted pyrroles by utilizing the Paal-Knorr synthetic protocol, achieving impressive yields under operationally simple reaction conditions without involving any precarious/dangerous catalysts or unsafe volatile organic solvents.
Stereoselective Postassembly CH Oxidation of Self-Assembled Metal-Ligand Cage Complexes
Holloway, Lauren R.,Bogie, Paul M.,Lyon, Yana,Julian, Ryan R.,Hooley, Richard J.
supporting information, p. 11435 - 11442 (2017/09/25)
Self-assembled Fe-iminopyridine cage complexes containing doubly benzylic methylene units such as fluorene and xanthene can be selectively oxidized at the ligand backbone with tBuOOH, with no competitive oxidation observed at the metal centers. The self-assembled cage structure controls the reaction outcome, yielding oxidation products that are favored by the assembly, not by the reactants or functional groups. Whereas uncomplexed xanthene and fluorene control ligands are solely oxidized to the ketone equivalents with tBuOOH, the unfavorability of the self-assembled ketone cages forces the reaction to form the tbutyl peroxide and alcohol-containing oxidation products, respectively. In addition, the oxidation is diastereoselective, with only single isomers of the cage assemblies formed, despite the presence of as many as 10 stereocenters in the final product. The self-assembled structures exploit self-complementary hydrogen bonding and geometrical constraints to direct the postassembly reactions to outcomes not observed in free solution. This selectivity is reminiscent of the fine control of post-translational modification seen in biomacromolecules.
