120569-12-2Relevant academic research and scientific papers
AuFeAg hybrid nanoparticles as an efficient recyclable catalyst for the synthesis of α,β- and β,β-dichloroenones
Mishra, Kanchan,Basavegowda, Nagaraj,Lee, Yong Rok
, p. 180 - 187 (2015)
A facile and green pioneer approach for the synthesis of stable trimetallic AuFeAg hybrid nanoparticles is described. This synthetic method is green-chemistry compatible and totally free of additives. The particle shape and size, surface chemistry, crystallinity, elemental composition, thermal and magnetic properties were investigated. The catalytic performance of the synthesized nanoparticles is also described. The hybrid nanocatalyst exhibited strong catalytic activity for the synthesis of α,β- and β,β-dichloroenones, which are important synthetic intermediates in the preparation of natural products. The reason behind the catalytic performance of nano sized hybrid particles was attributed to their high specific surface area. In addition, the nanocatalyst was easy to separate from the reaction mixture using an external magnet and could be reused for five consecutive reactions without any significant loss of activity. Using the present method, the trimetallic hybrid combination can be designed for similar types of catalytic reactions.
Preparation method of α,β- or β,β-dihaloenones from diazodicarbonyls
-
Paragraph 0031-0033; 0042-0043, (2017/08/30)
The present invention relates to a method for preparing andalpha;,andbeta;- or andbeta;,andbeta;-dihaloenone compounds from diazodicarbonyl compounds. According to the present invention, a diazo compound reacts with an oxalyl halide in the presence of a ruthenium catalyst so andalpha;,andbeta;- and andbeta;,andbeta;-dihaloenones can be synthesized through one-step reaction in an easy, simple and environmental manner. The synthesized andalpha;,andbeta;- and andbeta;,andbeta;-dihaloenones can be widely used for synthesis of intermediates of various drugs, natural materials, agricultural pesticides, dyes, etc. due to various biological activities.COPYRIGHT KIPO 2017
Ruthenium(II)-catalyzed protocol for preparation of diverse α,β- and β,β-Dihaloenones from diazodicarbonyls
Magar, Krishna Bahadur Somai,Lee, Yong Rok
, p. 3422 - 3432 (2015/02/02)
Efficient one-step syntheses of α,β- and β,β-dihaloenones were achieved by ruthenium(II)- catalyzed reactions between cyclic or acyclic diazodicarbonyl compounds and oxalyl chloride or oxalyl bromide in moderate to good yields. This methodology offers sev
An Efficient Synthesis of Some Substituted Vinylic Chloroformates: Reaction Scope and Limitations
Bowman, Mark P.,Senet, Jean-Pierre G.,Malfroot, Thierry,Olofson, R. A.
, p. 5982 - 5986 (2007/10/02)
2,2-Dichlorovinyl chloroformate is isolated in 50percent distilled yield when chloral is treated with phosgene and zinc dust in 2:1 methyl acetate/ether.The reaction has been extended to other α-chloro and α-bromo aldehydes and ketones in which both other α-positions are occupied by either halo and/or alkyl groups.The reaction fails with hydrogen in an α-position.Examples include the synthesis of Cl2C=C(Me)OC(=O)Cl in 23percent yield, MeC(Cl)=CHOC(=O)Cl (56percent, E:Z=1:1.1), Cl2C=C(C6H5)OC(=O)Cl (66percent), and 2-methyl-1-cyclohexenyl chloroformate (68percent).Similar treatment of α-halo esters gives only the C-acylated products expected from a Reformatsky type reaction, while ketenes are the well known products from α-halo acid chlorides.However, acyl cyanides and acyl phosphonates, with leaving groups intermediate between fluoride and alkoxide, are converted to chloroformates; e.g., Me2C=C(CN)OC(=O)Cl in 67percent yield and Me2C=COC(=O)Cl in 83percent yield.Carbonates and urethans from these chloroformates are of interest as monomers, pesticides, and chemical intermediates.
