1443151-85-6Relevant academic research and scientific papers
Para-Selective, Iridium-Catalyzed C-H Borylations of Sulfated Phenols, Benzyl Alcohols, and Anilines Directed by Ion-Pair Electrostatic Interactions
Montero Bastidas, Jose R.,Oleskey, Thomas J.,Miller, Susanne L.,Smith, Milton R.,Maleczka, Robert E.
, p. 15483 - 15487 (2019/10/11)
Para C-H borylations (CHB) of tetraalkylammonium sulfates and sulfamates have been achieved using bipyridine-ligated Ir boryl catalysts. Selectivities can be modulated by both the length of the alkyl groups in the tetraalkylammonium cations and the substituents on the bipyridine ligands. Ion pairing, where the alkyl groups of the cation shield the meta C-H bonds in the counteranions, is proposed to account for para selectivity. The 4,4′-dimethoxy-2,2′-bipyridine ligand gave superior selectivities.
Para-Selective C-H Borylation of Common Arene Building Blocks Enabled by Ion-Pairing with a Bulky Countercation
Mihai, Madalina T.,Williams, Benjamin D.,Phipps, Robert J.
, p. 15477 - 15482 (2019/10/11)
The selective functionalization of C-H bonds at the arene para position is highly challenging using transition metal catalysis. Iridium-catalyzed borylation has emerged as a leading technique for arene functionalization, but there are only a handful of strategies for para-selective borylation, which operate on specific substrate classes and use bespoke ligands or catalysts. We describe a remarkably general protocol which results in para-selectivity on some of the most common arene building blocks (anilines, benzylamines, phenols, benzyl alcohols) and uses standard borylation ligands. Our strategy hinges upon the facile conversion of the substrates into sulfate or sulfamate salts, wherein the anionic arene component is paired with a tetrabutylammonium cation. We hypothesize that the bulk of this cation disfavors meta-C-H borylation, thereby promoting the challenging para-selective reaction.
Ammonium Salt-Catalyzed Highly Practical Ortho-Selective Monohalogenation and Phenylselenation of Phenols: Scope and Applications
Xiong, Xiaodong,Yeung, Ying-Yeung
, p. 4033 - 4043 (2018/05/22)
An ortho-selective ammonium chloride salt-catalyzed direct C-H monohalogenation of phenols and 1,1′-bi-2-naphthol (BINOL) with 1,3-dichloro-5,5-dimethylhydantoin (DCDMH) as the chlorinating agent has been developed. The catalyst loading was low (down to 0.01 mol %) and the reaction conditions were very mild. A wide range of substrates including BINOLs were compatible with this catalytic protocol. Chlorinated BINOLs are useful synthons for the synthesis of a wide range of unsymmetrical 3-aryl BINOLs that are not easily accessible. In addition, the same catalytic system can facilitate the ortho-selective selenylation of phenols.
1,3,5-TRIAZINE-2-AMINE DERIVATIVES, PREPARATION THEREOF AND DIAGNOSTIC AND THERAPEUTIC USE THEREOF
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Page/Page column 19-20, (2013/07/05)
The present invention relates to compounds corresponding to formula (I) in which: - R1 represents a substituted phenyl; - R2 represents: - a substituted phenyl; - a heteroaromatic group, the said group being unsubstituted or substituted one or more times; - R3 represents a group Alk; - R4 represents a hydrogen atom or a (C1-C4)alkyl; - R5 represents a hydrogen atom, a (C3-C6)cycloalkyl or a (C1-C4)alkyl-O-Alk; - or alternatively R4 and R5, together with the nitrogen atom to which they are attached, constitute a heterocyclic radical chosen from: azetidin-1-yl, pyrrolidin-1-yl, piperid-1-yl, morpholin-4-yl; - R6 represents a group -COOAlk, a group -CONH2 or a group -NHSO2 Alk; - Alk represents a (C1-C4)alkyl, which is unsubstituted or substituted one or more times with a halogen atom; in the form of the base or of an acid-addition salt. Preparation process and diagnostic and therapeutic use
