52010-97-6Relevant articles and documents
o-Carborane as a Novel Protective Group for Aldehydes and Ketones
Nakamura, Hiroyuki,Aoyagi, Kouichi,Yamamoto, Yoshinori
, p. 780 - 781 (1997)
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IBX oxidation of benzenedimethanols in the presence of cucurbit[8]uril
Cong, Hang,Chen, Qiuju,Geng, Qingxia,Tao, Zhu,Yamato, Takehiko
, p. 545 - 549 (2015)
The cucurbit[8]uril (Q[8]) mediated oxidation of benzenedimethanols with o-iodoxybenzoic acid (IBX) in aqueous solution has been investigated, and the results reveal the supramolecular catalysis depends on the electronic and geometric structure of substrate. In the cases of o-benzenedimethanol (1a) and m-benzenedimethanol (1b), the IBX oxidation could be obviously enhanced by the addition of Q[8] at different extent. There is no observation of the catalytic activity of Q[8] when p-benzenedimethanol (1c) is subjected to the IBX oxidation. The addition amount of Q[8] is discussed herein, and the addition of more than 10% mol catalyst cannot improve the oxidation much more. The investigation of host-guest interactions by isothermal titration calorimetry implies the supramolecular catalysis is related to the formation of complexes between benzenedimethanols and cucurbit[8]uril. The supramolecular catalysis of Q[8] (cucurbit[8]uril) on the IBX (o-iodoxybenzoic acid) oxidation of o,m,p-benzenedimethanols in aqueous solvent and the host-guest interactions have been investigated.
Synthesis and characterization of complexes imparting N-pyridyl bonded meso-pyridyl substituted dipyrromethanes
Yadav, Mahendra,Singh, Ashish Kumar,Pandey, Rampal,Pandey, Daya Shankar
, p. 841 - 849 (2010)
The meso-pyridyl substituted dipyrromethane ligands 5-(4-pyridyl)dipyrromethane (4-dpmane) and 5-(3-pyridyl)dipyrromethane (3-dpmane) have been employed in the synthesis of a series of complexes with the general formulations [(η6-arene)RuCl2(L)] (η6-arene = C6H6, C10H14) and [(η5-C5Me5)MCl2(L)] (M = Rh, Ir). The reaction products have been characterized by microanalyses and spectral studies and molecular structures of the complexes [(η6-C10H14)RuCl2(4-dpmane)] and [(η5-C5Me5)IrCl2(3-dpmane)] have been determined crystallographically. For comparative studies, geometrical optimization have been performed on the complex [(η5-C5Me5)IrCl2(4-dpmane)] using exchange correlation functional B3LYP. Optimized bond length and angles are in good agreement with the structural data of the complex [(η5-C5Me5)IrCl2(3-dpmane)]. The complexes [(η6-C10H14)RuCl2(3-dpmane)], [(η5-C5Me5)RhCl2(3-dpmane)] and [(η5-C5Me5)IrCl2(3-dpmane)] have been employed as a transfer hydrogenation catalyst in the reduction of aldehydes. It was observed that the rhodium and iridium complexes mentioned above are more effective in this regard in comparison to the ruthenium complex.
One-pot synthesis and PEGylation of hyperbranched polyacetals with a degree of branching of 100%
Liu, Na,Vignolle, Joan,Vincent, Jean-Marc,Robert, Frederic,Landais, Yannick,Cramail, Henri,Taton, Daniel
, p. 1532 - 1542 (2014)
The Bronsted acid-catalyzed polytransacetalization of hydroxymethylbenzaldehyde dimethylacetal (1), a commercially available AB 2-type monomer, led to hyperbranched polyacetals (HBPA's) with a degree of branching (DB) around 0.5 by forming methanol as byproduct. In sharp contrast, the polyacetalization of the nonprotected homologue, namely, hydroxymethylbenzaldehyde (2), yielded HBPA's with DB = 1, by forming water as byproduct, under the same acidic conditions. This major difference arises from the instability of the initially formed hemiacetal intermediates, which react faster than aldehyde moieties, driving the polyacetalization toward the quantitative formation of dendritic acetal units. This represents a rare example of defect-free hyperbranched polymer synthesis utilizing a very simple AB 2-type monomer. Bronsted acid catalysts included p-toluenesulfonic, camphorsulfonic, and pyridinium camphorsulfonic acids. Trapping of the water generated during polyacetalization of 2 was accomplished using molecular sieves regularly renewed, which allowed achieving polymers of relatively high molar masses. These HBPA's with DB = 1 featuring multiple aldehyde functions at their periphery were further derivatized into PEGylated HBPA's, using linear amino-terminated poly(ethylene oxide)s of different molar masses. This led to submicrometric sized HBPA's with a core-shell architecture. Finally, HBPA derivatives could be readily hydrolyzed under acidic conditions (e.g., pH = 4), owing to the acid sensitivity of their constitutive acetal linkages.
Efficient and chemoselective hydrogenation of aldehydes catalyzed by well-defined PN3-pincer manganese(ii) catalyst precursors: An application in furfural conversion
Gholap, Sandeep Suryabhan,Dakhil, Abdullah Al,Chakraborty, Priyanka,Li, Huaifeng,Dutta, Indranil,Das, Pradip K.,Huang, Kuo-Wei
supporting information, p. 11815 - 11818 (2021/11/30)
Well-defined and air-stable PN3-pincer manganese(ii) complexes were synthesized and used for the hydrogenation of aldehydes into alcohols under mild conditions using MeOH as a solvent. This protocol is applicable for a wide range of aldehydes containing various functional groups. Importantly, α,β-unsaturated aldehydes, including ynals, are hydrogenated with the CC double bond/CC triple bond intact. Our methodology was demonstrated for the conversion of biomass derived feedstocks such as furfural and 5-formylfurfural to furfuryl alcohol and 5-(hydroxymethyl)furfuryl alcohol respectively.
Synthesis and evaluation of novel α-aminoamides containing benzoheterocyclic moiety for the treatment of pain
Cheng, Jingchao,He, Junlin,Ren, Fengxia,Ren, Fengzhi,Shi, Weiguo,Tong, Kun,Yu, Zixing,Zhang, Ruotian,Zhang, Tao,Zhang, Yatong
, (2021/06/15)
Novel α-aminoamide derivatives containing different benzoheterocyclics moiety were synthesized and evaluated as voltage-gated sodium ion channels blocks the treatment of pain. Compounds 6a, 6e, and 6f containing the benzofuran group displayed more potent in vivo analgesic activity than ralfinamide in both the formalin test and the writhing assay. Interestingly, they also exhibited potent in vitro anti-Nav 1.7 and anti-Nav 1.8 activity in the patch-clamp electrophysiology assay. Therefore, compounds 6a, 6e, and 6f, which have inhibitory potency for two pain-related Nav targets, could serve as new leads for the development of analgesic medicines.
