A simple and efficient method for the synthesis of gem-diacetates from aldehydes and ketones catalysed by gallium triiodide

2005 ◽  
Vol 2005 (10) ◽  
pp. 659-660 ◽  
Author(s):  
Peipei Sun ◽  
Zhixin Hu
Keyword(s):  
Acetic Anhydride ◽  
Ambient Temperature ◽  
Efficient Method ◽  
Carbonyl Compounds ◽  
Aldehydes And Ketones

Aldehydes or ketones reacted with acetic anhydride in dichloromethane at ambient temperature to produce gem-diacetates in good to excellent yields in the presence of gallium triiodide, which was generated in situ from gallium and iodine. This catalyst was also useful for the deprotection of carbonyl compounds in the presence of water.

Regioselective Addition of Quinoline Derivatives to Carbonyl Compounds via Palladium-Catalyzed Umpolung with Diethylzinc

Synthesis ◽  
2019 ◽  
Vol 51 (08) ◽  
pp. 1795-1802 ◽  
Author(s):  
Yohei Matsumoto ◽  
Kosuke Yamamoto ◽  
Masami Kuriyama ◽  
Koyo Nishida ◽  
Osamu Onomura
Keyword(s):  
Efficient Method ◽  
Palladium Catalyst ◽  
Carbonyl Compounds ◽  
Quinoline Derivatives ◽  
Regioselective Addition ◽  
Aldehydes And Ketones ◽  
Palladium Catalyzed ◽  
Selective Addition

An efficient method for the C-4-selective addition of quinoline derivatives to carbonyl compounds is described. The combination of 2-ethoxy-1-ethoxycarbonyl-1,2-dihydroquinolines (EEDQs) with a palladium catalyst and diethylzinc generates nucleophilic allyl species which undergo addition to various aldehydes and ketones. C-4-Substituted quinoline derivatives are obtained in high to excellent yields with moderate diastereoselectivities.

SEM of non-coated hepatocellular cytoskeleton of perfused livers

1984 ◽  
Vol 42 ◽  
pp. 306-307
Author(s):  
S.W. French ◽  
N.C. Benson ◽  
C. Davis-Scibienski
Keyword(s):  
Ambient Temperature ◽  
Critical Point ◽  
Protease Inhibitors ◽  
Metal Deposition ◽  
Heat Damage ◽  
Detergent Extraction ◽  
Cytoskeletal Elements ◽  
Triton X ◽  
Excised Tissue

Previous SEM studies of liver cytoskeletal elements have encountered technical difficulties such as variable metal coating and heat damage which occurs during metal deposition. The majority of studies involving evaluation of the cell cytoskeleton have been limited to cells which could be isolated, maintained in culture as a monolayer and thus easily extracted. Detergent extraction of excised tissue by immersion has often been unsatisfactory beyond the depth of several cells. These disadvantages have been avoided in the present study. Whole C3H mouse livers were perfused in situ with 0.5% Triton X-100 in a modified Jahn's buffer including protease inhibitors. Perfusion was continued for 1 to 2 hours at ambient temperature. The liver was then perfused with a 2% buffered gluteraldehyde solution. Liver samples including spontaneous tumors were then maintained in buffered gluteraldehyde for 2 hours. Samples were processed for SEM and TEM using the modified thicarbohydrazide procedure of Malich and Wilson, cryofractured, and critical point dried (CPD). Some samples were mechanically fractured after CPD.

Nickel-Catalyzed Regioselective Hydroalkylation of 1,3-Dienes with Hydrazones

2019 ◽  
Author(s):  
Leiyang Lv ◽  
Dianhu Zhu ◽  
Zihang Qiu ◽  
Jianbin Li ◽  
Chao-Jun Li
Keyword(s):  
Catalytic Method ◽  
Unsaturated Hydrocarbons ◽  
Carbon Nucleophiles ◽  
Aryl Aldehydes ◽  
Aldehydes And Ketones ◽  
Sterically Hindered

Hydroalkylation of unsaturated hydrocarbons with unstablized carbon nucleophiles is difficult and remains a major challenge. The disclosed examples so far mainly focused on the involvement of heteroatom and/or stabilized carbon nucleophiles as efficient reaction partners. Reported here is an unprecedented regioselective nickel-catalyzed hydroalkylation of 1,3-dienes with hydrazones, generated in situ from abundant aryl aldehydes and ketones and acted as both the sources of unstabilized carbanions and hydride. With this strategy, both terminal and sterically hindered internal dienes are hydroalkylated efficiently in a highly selective manner, thus providing a novel and reliable catalytic method to construct challenging C(sp3)-C(sp3) bonds.

scholarly journals Back Cover: In Situ Observation of Non‐Classical 2‐Norbornyl Cation in Confined Zeolites at Ambient Temperature (Angew. Chem. Int. Ed. 9/2021)

2021 ◽  
Vol 60 (9) ◽  
pp. 4952-4952
Author(s):  
Xiaomin Tang ◽  
Wei Chen ◽  
Xianfeng Yi ◽  
Zhiqiang Liu ◽  
Yao Xiao ◽  
...  
Keyword(s):  
Ambient Temperature ◽  
In Situ Observation ◽  
Back Cover

scholarly journals Copper(I) Chloride/Kieselguhr: A Versatile Catalyst for Oxidation of Alkyl Halides and Alkyl Tosylates to the Carbonyl Compounds

1999 ◽  
Vol 23 (7) ◽  
pp. 434-435
Author(s):  
Mohammed M. Hashemi ◽  
Yousef Ahmadi Beni
Keyword(s):  
Carbonyl Compounds ◽  
Alkyl Halides ◽  
Aldehydes And Ketones ◽  
High Yields

Copper(I) Chloride adsorbed on Kieselguhr in the presence of oxygen catalyses oxidation of alkyl halides and alkyl tosylates to the aldehydes and ketones in high yields.

A facile one pot route for the synthesis of imide tethered peptidomimetics

2016 ◽  
Vol 14 (2) ◽  
pp. 556-563 ◽  
Author(s):  
Veladi Panduranga ◽  
Girish Prabhu ◽  
Roopesh Kumar ◽  
Basavaprabhu Basavaprabhu ◽  
Vommina V. Sureshbabu
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Efficient Method ◽  
One Pot ◽  
Protected Amino Acid

A simple and efficient method for the synthesis of N,N’-orthogonally protected imide tethered peptidomimetics is presented. The imide peptidomimetics were synthesized by coupling the in situ generated selenocarboxylate of Nα-protected amino acids with Nα-protected amino acid azides in good yields.

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