64543-53-9Relevant academic research and scientific papers
Nickel-catalyzed cross-coupling of aldehydes with aryl halides: Via hydrazone intermediates
Tang, Jianting,Lv, Leiyang,Dai, Xi-Jie,Li, Chen-Chen,Li, Lu,Li, Chao-Jun
, p. 1750 - 1753 (2018/02/21)
Traditional cross-couplings require stoichiometric organometallic reagents. A novel nickel-catalyzed cross-coupling reaction between aldehydes and aryl halides via hydrazone intermediates has been developed, merging the Wolff-Kishner reduction and the classical cross-coupling reactions. Aromatic aldehydes, aryl iodides and aryl bromides are especially effective in this new cross-coupling chemistry.
Cross-Coupling of Phenol Derivatives with Umpolung Aldehydes Catalyzed by Nickel
Lv, Leiyang,Zhu, Dianhu,Tang, Jianting,Qiu, Zihang,Li, Chen-Chen,Gao, Jian,Li, Chao-Jun
, p. 4622 - 4627 (2018/05/22)
A nickel-catalyzed cross-coupling to construct the C(sp2)-C(sp3) bond was developed from two sustainable biomass-based feedstocks: phenol derivatives with umpolung aldehydes. This strategy features the in situ generation of moisture/air-stable hydrazones from naturally abundant aldehydes, which act as alkyl nucleophiles under catalysis to couple with readily available phenol derivatives. The avoidance of using both halides as the electrophiles and organometallic or organoboron reagents (also derived from halides) as the nucleophiles makes this method more sustainable. Water tolerance, great functional group (ketone, ester, free amine, amide, etc.) compatibility, and late-stage elaboration of complex biological molecules exemplified its practicability and unique chemoselectivity over organometallic reagents.
Synthesis of structurally diverse diarylketones through the diarylmethyl sp3 C-H oxidation
He, Chao,Zhang, Xiaohui,Huang, Ruofeng,Pan, Jing,Li, Jiaqiang,Ling, Xuege,Xiong, Yan,Zhu, Xiangming
, p. 4458 - 4462 (2014/08/05)
Under open-flask conditions, an efficient method to assemble a series of diversely functionalized diarylketones in the presence of commercially available NBS has been developed. Yields of up to 99% have been achieved employing diarylmethanes as starting material. Based on 18O-labeled experiment, the addition of stoichiometric water eventually leads to excellent yields in all carbonylation cases.
Reduction of carbonyl to methylene: Organosilane-Ga(OTf)3 as an efficient reductant system
Surya Prakash,Do, Clement,Mathew, Thomas,Olah, George A.
experimental part, p. 507 - 511 (2012/01/04)
Direct carbonyl reduction to methylene has been achieved by mild reductant system obtained from the combination of organosilane and gallium (III) trifluoromethanesulfonate {Ga(OTf)3}, a water tolerant, recyclable, catalyst. Among a series of organosilanes studied, dimethylchlorosilane (Me 2SiHCl, DMCS) showed the highest efficiency. Both aromatic and aliphatic ketones were effectively reduced to the corresponding methylene products with high functional groups tolerance, under very mild conditions in a relatively short period of time with good to excellent yields. Graphical Abstract: [Figure not available: see fulltext.]
Synthesis and structure-activity relationship of the first nonpeptidergic inverse agonists for the human cytomegalovirus encoded chemokine receptor US28
Hulshof, Janneke W.,Casarosa, Paola,Menge, Wiro M. P. B.,Kuusisto, Leena M. S.,Van Der Goot, Henk,Smit, Martine J.,De Esch, Iwan J. P.,Leurs, Rob
, p. 6461 - 6471 (2007/10/03)
US28 is a human cytomegalovirus (HCMV) encoded G-protein-coupled receptor that signals in a constitutively active manner. Recently, we identified 1 {5-(4-(4-chlorophenyl)-4-hydroxy-piperidin-1-yl)-2,2-diphenylpentanenitrile} as the first reported nonpeptidergic inverse agonist for a viral-encoded chemokine receptor. Interestingly, this compound is able to partially inhibit the viral entry of HIV-1. In this study we describe the synthesis of 1 and several of its analogues and unique structure-activity relationships for this first class of small-molecule ligands for the chemokine receptor US28. Moreover, the compounds have been pharmacologically characterized as inverse agonists on US28. By modification of lead structure 1, it is shown that a 4-phenylpiperidine moiety is essential for affinity and activity. Other structural features of 1 are shown to be of less importance. These compounds define the first SAR of ligands on a viral GPCR (US28) and may therefore serve as important tools to investigate the significance of US28-mediated constitutive activity during viral infection.
Electrophilic Aromatic Substitution. 8. A Kinetic Study of the Friedel-Crafts Benzylation Reaction in Nitromethane, Nitrobenzene, and Sulfonate. Substitutient Effects in Friedel-Crafts Benzylation
DeHaan, Franklin P.,Delker, Gerald L.,Covey, William D.,Ahn, Jeffrey,Anisman, Mark S.,et al.
, p. 7038 - 7046 (2007/10/02)
Kinetic studies have been made of the reaction of benzyl chloride with benzene and/or toluene catalyzed by TiCl4 in nitromethane and in nitrobenzene and catalyzed by SbCl5 in nitromethane and sulfolane.The reaction are zero order in aromatic, first order in benzyl chloride, and either second order in TiCl4 or first order in SbCl5.Competitively determined kT/kB values range from 2.1 to 3.1 and product toluene isomer percentages were ortho 42-46percent, meta 4.7-6.4percent, and para 48-52percent for all four reactions.The reactions do not fit Brown's selectivity relationship (BSR), giving slope b values in the range 0.6-0.8.Competitive or noncompetitive kinetic studies are reported for Friedel-Crafts benzylation reactions with p-chloro, 3,4-dichloro, p-methyl, and p-nitrobenzyl chlorides in nitromethane.The AlCl3-catalyzed reactions of p-chloro- and 3,4-dichlorobenzyl chloride are both zero order in aromatic and do not follows BSR.However, the TiCl4-catalyzed p-xylyl chloride reaction fits Brown's relationship even though it is also zero ordered in aromatic.The p-nitrobenzyl chloride reaction catalyzed by AlCl3 is first order in aromatic hydrocarbon and also obeys Brown's relationship.These mechanistic differences are rationalized in terms of Jencks' approach: the xylyl cytion is diffusionally equilibriated and shows relatively high substrate selectivity, the less stable p-chloro- and 3,4-dichlorobenzyl cations react faster than they diffuse thus exhibiting little selectivity, while with p-nitrobenzyl chloride an SN2 displacement mechanism is preferred.
